What host cores did Dolores take with her?

It has yet to be determined or presented to the audience.

ENTERTAINMENT WEEKLY: Do you know who each of those balls represent in Dolores’ purse? Or is your cast on edge about which characters Dolores found worthy of survival?

JONATHAN NOLAN: We’ve had some interesting conversations. It’s a large ensemble cast and sadly we’re saying goodbye to some people at the end of this season. But as always with this show, who remains and who doesn’t is something we’re having a lot of fun with. There’s going to be a bit of a wait for a third season but we want to surprise and hopefully delight people with the way things progress.

EW: When we see Dolores walking with Charlotte out of the room at the end on the mainland, does that mean there are now two Doloreses played by different actors?

JN: Ehhh, not really. The question of who’s who and what we’re looking at is something we’re excited to play with. We’re excited to withhold a little from the audience but … it’s complicated. http://ew.com/tv/2018/06/24/westworld-season-2-finale-interview/

However, if one watches the final pre-credit scene, some notice that they way Tessa Thompson's character carries herself, especially her weapon, is rather reminiscent to Angela, but this is pure speculation at this point