Ironclad guarantee you'd also see a Star Trek RPG at some point, given that back in that era (pre ST:TNG) Trek still had a loyal following and there was in some cases a fairly deep divide between the ST and SW fanbases.
Oh yeah, once licensed RPGs happen, we definitely get Star Trek. I would bet on it arriving later than the Star Wars RPG in this alternate timeline, though.
That said, just realized that in a sense, Star Trek has "character classes" - command, security/engineering/ops, science/medical. Be kind of funny if Star Wars supplied the tropes for this theoretical first SF-based RPG, but Star Trek supplied the structure...
It might be more heavily influenced by the prequels.
Very true; it might even be created as a tie-in to the prequels! Assuming, of course, that Star Wars stays on schedule with less support from an expanded universe in the late 1980s/early 1990s.
I have to wonder about the monsters. Would they be based more in folklore, with more of an effort to get the folklore right? Or would they decide to make monster elements, like in Pokemon and other similar games, and then mash them together in weird ways. With certain monster elements being weak to or resistant against certain colors of magic...
(Y'know, technically speaking, back in editions before the idea of monster advancement and just upping the Hit Dice of the monster, the orc was the "evolved" form of the goblin, and the ogre was the "evolved" form of the orc...)
As I said before, I'm not sure we get Pokémon, due to the different path RPG-style video games take without D&D in the 1970s. (If we do see a version of Pokémon, it's probably focused much more on collecting than fighting; the designer's stated inspiration was bug-collecting.)
I'd expect folklore to be as much a factor for a later, alternate D&D as it was for Gygax and company in the 1970s - certainly significant, but not much more accurate. (Accuracy is largely a modern concern - look at folklore-based fiction from the 1980s, 1990s, and even 2000s, they're often just as loose. Disney's approach is more typical.)
I could see monster choices also hewing closer to paranormal/cryptozoology stuff, since that was popular on and off in the 1970s through 1990s. Bigfoot and such.