Many American wrestlers become far, far more popular overseas than they ever were in the US — in some cases it's hard to say that this trope applies, because they often spend enough time in another country to be foreign stars rather than American stars; still, it is astonishing how much more popular some wrestlers can be abroad than they were at their American peak.
Stan Hansen is the ultimate example; a moderately well known figure in American wrestling history, but one of the biggest stars in the history of Japanese wrestling.
Matt Bloom, known as Albert and A-Train in WWE, went to New Japan Pro Wrestling after his release and became their resident monster Giant Bernard. He later returned to America as the "Japanese" brute Tensai, whereupon he ironically faced Mighty Whitey accusations from many Americans.
Mark Jindak was a rather generic midcarder in WWE (and WCW before that). He finally found stardom as Marco Corleone in CMLL.
This is actually an invoked or enforced trope. In the 80's, Japanese promotions paid through the nose for American main event talent like Stan Hansen, Bruiser Brody, The Road Warriors, and Jimmy Snuka. With wrestling's popularity and money on the wane in Japan while simultaneously going up in the US, Japanese wrestling promoters made a conscious decision to build up American wrestlers who could do the style but had never made it out of the preliminary ranks, like Scott Norton or Vader.
This was responsible for (briefly) resurrecting Hulk Hogan's career as a face in WWE. When they set up the match between Hogan and The Rock in shows being filmed in the US, Hogan was clearly playing the heel (coming off his stint in WCW) and Rock the face. The actual match was at WrestleMania X8 in Toronto, where Hogan was so over with the crowd, mostly due to nostalgic reasons, that the announcers were clearly stunned by the crowd's reaction in treating Hogan as the face and the Rock as, at best, the Worthy Opponent.
Bret Hart is one of the most popular wrestlers in WWE's European and Asian markets (moreso than Hogan or Austin), due to being the main TV star when WWE started exporting its programming outside of North America. Similarly, Dave Bautista was a big star in their Mexican markets due to the perception that he was a Mexican-American (he's actually Filipino).
Ricky Marvin is a luchador. In Mexico, he was... alright, but just a generic midcarder. During some interpromotional work with Ultimo Dragon and Toryumon, he decided to make the jump over to Japan, where he's been a fixture in Pro Wrestling NOAH's Junior Heavyweight division since 2003.
Lucha Libre in general is very popular in Japan, mainly due to native stars who toured Mexico in their "journeyman" stage (when wrestling was big, it was common to send preliminary wrestlers abroad to learn different types of wrestling) and brought the style back, as well as popular foreigners like Mil Mascaras. There have been a number of independent lucha promotions in Japan over the years. On the flip side, Satoru "Tiger Mask" Sayama made a very brief tour in Mexico before returning home, and is still talked about by Mexican TV commentators as one of the best and most popular luchadors ever, thirty years later.
MMA is a curious example. In Japan, it's strongly tied to professional wrestling (thanks to the long legacy of Antonio Inoki and his apprentices), promoted as professional wrestling, sometimes features shoot (real) and worked (fake) matches on the same card, and it's no big deal for a "shoot" fighter to "work" a loss to build another star. In the United States, UFC runs like hell from any association with professional wrestling or implications of fixed fights, and former professional wrestlers are often hated by the MMA community, regardless of how good at MMA they are, such as former UFC heavyweight champion and WWE superstar Brock Lesnar.
Ironically, UFC (and mixed martial arts itself) may had never hit mainstream success if it wasn't for UFC 40, which was headlined by Tito Ortiz and Ken Shamrock, who had started out in pro wrestling, moved to MMA, but became popular after his stint in WWE wrestling during the Attitude Era and later became a household name at that time thanks to 20/20 and the WWF.
Bob Sapp was the center of Japan's media. He had a music video, endorsed hundreds of products, and their tiny people lined up for the honor of being eaten by him. He was the Japanese equivalent of the '85 Bears, Crocodile Dundee, Muhammad Ali, and the California Raisins all in one.
Yoshihiro Akiyama. In the UFC, he's an up-and-coming middleweight with an exciting intro who has won "Fight of the Night" bonuses in all of his appearances. In his home country of Japan, he's considered a disgraceful cheat after greasing his legs in a fight with legend Kazushi Sakuraba.
This even happened with different regions in the same country during the territorial days of wrestling. For example, Bill Watts built the Louisiana-Oklahoma-Arkansas Mid-South territory around big, grizzled he-man wrestlers. At a loss as to how to turn around his business during a down period (1983), he brought in a bunch of young pretty-boy tag team wrestlers and a new booker from the Memphis territory, which had a surfeit of those wrestlers at the time. With booker Bill Dundee providing what had been, to Memphis, comedy finishes (such as an abortion known as the "Blind Man's Battle Royal," an all-blindfold match treated as comedy fodder in Memphis; doing the same match in New Orleans had fans driving ambulances to the arena, sure that someone would be seriously hurt or dead by the end), Watts was able to make 1984 his most profitable year in the history of the territory.
Japanese professional wrestling (particularly in the '90s) had a dedicated fanbase among American Smart Marks, due to the general low quality of the American product at the time. Independent group Ring of Honor even brought the top stars of Pro Wrestling NOAH to the States to appeal to this crowd, and before that, ECW (the original) brought in a number of veterans from Japanese garbage promotions like FMW and IWA.
Simiarly British wrestling from the World of Sport era is beginning to gain a bit of cult following with American SmartMarks,but in the UK, due to the WWF eclipsing the entire British wrestling scene the early '90s, many wrestlers from that era are all but forgotten. CHIKARA even brought in 71 year old Johnny Saint as a special guest.
With limited skills and a bizarre look, young Ian Richard Hodgkinson was unable make any name for himself in the independent circuit in his native Canada. After several years, he went down to Mexico for work, and soon became a massive star in CMLL as Vampiro. Subsequent attempts to break out in WCWnote Vampiro would reach the upper midcards and even work a main event angle with Sting, but when WCW closed WWF didn't want him and Japan would lead to some success but nothing close to his stardom in Mexico. Many Americans mistake him for a Mexican national; the slightly Latino accent he developed does nothing to help the misconception.
This goes also for his longtime professional and personal rival Konnan. Konnan (real name Charles Ashenoff, a Cuban-American) was a longtime midcarder for WCW, but was a main event talent in Mexico (and was able to branch out into non-wrestling Mexican TV and music careers as well).
Norman Smiley is best remembered in the United States as a hardcore comedy act in WCW. In Mexico during the early 90s, he was massively over with the crowd and a main-event talent.
Literalized for PN News and Salvatore Bellomo. News, real name Paul Neu, while strictly a midcarder in WCW, moved to Germany in the 2000s and is a major name there. Of course, much like Triple H, he married the promoter. After unsuccessful runs in WWE and ECW, Bellomo moved to Belgium and became a top guy there.
Masato Tanaka got hugely popular in the U.S. after debuting in ECW in 1998, to the point that even Shane Douglas, who rarely had anything good to say about anyone, had to admit while on commentary that Tanaka had gotten over with the ECW fans faster than anyone he'd ever seen. Tanaka was so over that he would cut entire promos in Japanese and the mutants would cheer their heads off.
NWA Ring Warriors, an attempt to make a version of New Japan Pro Wrestling for an American Audience by Hiro Matsuda with help from Howard Brody got more viewers than both WCW and WWF during the 1990s...in Europe and Africa (and some of Asia). It was virtually unknown in the USA until 2011, and even then, mostly known to fans in Florida.
The Californian based Empire Wrestling Federation, Ultimate Pro Wrestling and All Pro Wrestling were peculiarly popular in Japan despite being foreign indies. ARSION, Pro Wrestling Zero 1 and even some larger promotions such as New Japan and AJW would send personal invitations to many of their wrestlers, including some rookies fresh out of Jesse Hernandez's School Of Hard Knocks. This in turn raised some level of awareness of Japanese companies ARSION, Zero 1 and Fighting Opera HUSTLE among fans in fifty states.
Ring of Honor an TNA are very popular in the United Kingdom, the former setting ticket gross records, the latter having local wrestling promoters name events after TNA after pay per views and getting its own British reality show.
Among ROH wrestlers, BJ Whitmer was one who was part of the invasion against IWA Puerto Rico but the fans ended up loving him.
TNA's X division turned out to be a surprise hit in the Japanese markets, to the point several Japanese wrestlers would use the tapes for training. Doesn't help that more than a few Japanese promotions up to and including NJPW were in something of a Dork Age at the time.
Professional wrestling has become a particularly quirky hit in the South American country of Bolivia. In part this is due to the lucha libre influence from Mexico, but the Bolivians are also huge fans of WWE (John Cena, Batista, and Rey Mysterio are particular favorites)...and, oddly enough given the somewhat chauvinistic Bolivian culture, the WWE Divas. Indeed, the Bolivians seem to delight in giving women's wrestling a native twist by having their cholitas (their equivalent word for "Divas") compete in the English bowler hats and long, ruffled skirts that comprise the traditional costume of Aymara Indian women (which is otherwise hardly ever worn in modern-day Bolivia). Amusingly enough, some of the cholitas could teach their North American counterparts a trick or two: one match witnessed by a reporter writing for National Geographic about the phenomenon booked several cholitas against a gigantic Egyptian mummy named "Ramses"; for comparison, just try to imagine Bella Twins taking on The Undertaker!