Is it possible to romance Shadow Heart or Karlach after Act 1

[76561199371159827]

I cleared the goblin Camp really early so my relation with both wasnt that high so i couldnt use the romance option for them at the party. Now im deep into act 2 and have really high relation with both of them but i cant talk to them about romance, even though i repaired karlach engine completly and shadow heart trust me enough to show me her Memories. Wyll and Gale on the other hand get many cutscenes without me doing anything. Is there anything i can still do or do i need to start a new run for these romance paths?

[Rex is back, baby!]

Yes.
Finish SH's act 2 quest. She doesn't really 'consider' romance until after that. Well, one pathway. The other pathway she's unromanceable.

Karlach will jump you as soon as she wants to.

[FoxFox]

Interesting question, I really don't know. The infernal engine things does play an important part in the Karlach romance the way I played it (the first scene is about you not being able to touch each other at all). The second scene requires you to have improved the engine for the second time in the Shadowlands and triggers in response to getting her that fix. I'm not sure what happens if the first scene never triggered.

Shadowheart only kind of warmed up to me after I had already gone for Karlach. But I did have an interaction with her during Act 2 that seemed to be leading up to romance. This was after she shared her memory with me. Seems like the Shadowheart romance would have still been an option if I hadn't already committed to Karlach.