Bad Export for You: A minor example, as it is limited to the demo version, but the Project Mirai Deluxe demo could only be played once in Europe, while the American version can be played 30 times. Later subverted when SEGA admitted that this wasn't intentional and that players who want to play the demo more than once should contact the eShop customer service.
Colbert Bump: General rule of thumb is that if a song with relatively little popularity makes it into a Project DIVA game, expect it to experience a popularity spike.
Early-Bird Cameo: In Project Diva on PSP, Hello Planet has a mini-game version based on the non-extend music video. This mini-game can unlock a second, alternative ending for the music video it's based on. As of the end of 2015, it has not appeared in any game with an alternate PV.
Finally ended with Miku Flick and Project DIVA F, both versions, although the PSP and first 3DS game remain Japan-only. DIVA Arcade is available outside of Asia in select arcades (specifically, some of Round 1's U.S. branches).
Just a day before Project Diva f 2nd was released in Japan, SEGA announced a physical release of the game in both North America and Europe. Unlike Project Diva f, Both the Japanese AND English versions are being released in parallel to each other, rather than staggered.
Also, the DLC is being released, semi-randomly, near constantly for Project Diva F 2nd in America and Europe.
In an inverse, pre-order DLC packs for F 2nd not included in any of the current Japanese DLC packs are the Americana module for America and Europe versions, and the China module for China version.
Averted as of February 2015, where all foreign pre-order DLC costumes were added to Project Diva F 2nd in all territories.
Project Mirai Deluxe was meant to end this for 3DS owners by having the game come out in America and Europe a few days before the Japanese version, in late May 2015. However, the game was then delayed to September in these regions, while the Japanese version still released in May.
The music video for "The MMORPG Addict's Anthem" in Project Diva F takes place (and debuted) in Phantasy Star Online 2 and features Miku dressed as a FOnewearl. Project Diva F was released overseas in 2013, while PSO2's North American localization remains in Development Hell to this day.
The depressing thing being here that Phantasy Star Online 2 was known to have a english translation in 2012. SEGA apparently cancelled it due to the same cash shop issues that killed Phantasy Star Universe on XBOX 360.
Recursive Adaptation: The video for "Black★Rock Shooter" appears primarily inspired by the anime Black★Rock Shooter than the original PV itself (down to BRS's signature blue flame in her left eye and Black Rock Shooter's cameo), as well as the song being the version from the 2012 anime rather than the original. So it winds up being that Project DIVA F channeled the Black★Rock Shooter anime, which channeled the OVA, which channeled the original song.