Work is being dumb so I'm gonna throw out the few things I have off the top of my head and probably come back later to cover the rest.
Shaun - DESMOND SAYS HI JERK. (I ended up using Sam Witwer so you have to try not to see Scott SORRY.) I'm gonna enjoy throwing the ezios at him. The older one will be more respectful than the teenager. Ezia will probably be somewhere in the middle, trying to wind him up whenever she gets a chance. Shepard's been here ten months and I've decided he was my experiment on by Templars person so maybe they're friends by now?
Adaar - HAWKE SAYS HI and thanks for not leaving my ass in the fade. She's been in Kirkwall helping Varric for awhile. I like to think they got along for the most part? Her snarkiness notwithstanding. I'd love it if her and Porthos were friendly. He's a modern au but he still respects the hell out of the whole swordfighting business.
Jacobs - I mean we've talked about this, but I'm gonna throw all the ezios at the both of them, that's a given. Bb!Jesse will probably harass personality swap Jacob. Desmond and older Jacob should be buddies.
Gabes - bb!Jesse can't wait to meet Gabi! I'll dump him in LA in a few weeks to annoy the other one. I told Andrea Ana will be happy about the boys but waiting for it to go bad. She'll love the girls though! She's in NYC for now, subject to change. I'd like it if Shepard's gotten a chance to get to know Gabe a bit. He's been here 10 months, they're both soldiers who are capable of hard decisions and shit.
Zarya - ooh we have to figure out if mccree knows her. Would she have worked with the van helsing types? Either way he'll like her. Porthos will LOVE her. Bb!Ezio is like O_O lmfao but he'll be nice-ish because she's INTIMIDATING AF.