Trope Finder

First is probably Noble Demon.

Second is... kind of complicated. What is "GBG"? What is "NHSM"? What is the question, exactly?

First seems like a legit example of Affably Evil (villain is genuinely nice on a personal level but still commits evil acts).

What are you trying specifically to trope with the second one? I think it could be a variant of Self-Destructing Security but I'm not sure.

For the first, when it's specifically that they show hospitality, No, Mr. Bond, I Expect You to Dine (when there's a distinct note of "I will have you shot if you don't play along") or Did We Just Have Tea with Cthulhu? (The villain really does just want to show off his wine collection and have a nice chat, with no intention of violating Sacred Hospitality.)

From what's been posted so far, the first one is probably Affably Evil, while the second one might be less Self-Destructing Security and more of a cross between Self-Destruct Mechanism and Bait-and-Switch (it looks like it's going to flee, but explodes instead). In fact, the second scenario might in fact be two tropes in and of itself: The ship exploding is a textbook bait and switch, while the other aspect is that the villain's seemingly useless accessory turns out to have a purpose in the end.

Another example of the first trope is a Space Engineers ship by the name of The Revenant that I used to use as my flagship. It may've been an ominous black warship that would rather blast you to bits than befriend you, but if you came across us at a resupply station, odds are we're there for the same reason as you. Though if you did decide to attack the ship, you'd better hoped you weren't in the path of it's dorsal-bow^note top-front turret array, or you might've found yourself free-floating amidst the various bits of scrap that used to be your ship. And if you did manage to dodge the turrets, a dozen-strong fighter squad would've been ready to chase you down.^note Of course, this means nothing since a programming error led to me accidentally overwriting the ship in the process of moving it to a new version of the same map. And since the original, unmodified ship is on an admittedly ancient version of the game, my version can't be restored, so it's basically lost forever unless someone can somehow load the older save just long enough to convert it's code to the current version. If you can do that, then reupload it to the workshop, both me and the map creator would be grateful.