From Soren's perspective; he's mostly indifferent, but nonethless protective of them.

He's aware of the... awkwardness of his situation but doesnt want to simply act as a replacement for the previous WoL - however he also doesnt know how to bridge the gap between he and the scions.

Alisaie does however recognise Soren's strength; and although she will not admit it, is also interested in his past as an Arcadion fighter - she secretly wants to spar with him.

She has a more combative relationship with Soren - often comparing him to the previous WoL, or teasing/goading him.

Alisaie on the other hand is very agitated by Soren's presence (though this softens somewhat by the end of 7.3). She is disturbed by the fact that he shares the same name as her former friend, as well as being a shard of that very same person, as if the world was playing a cruel joke.

Alphinaud is much more at ease with him than Alisaie, but was initially apprehensive upon their first meeting. He regards Soren with honest curiosity, and wants to learn more about him.

Alphinaud strives to teach him about the history of the scions (and the WoL that came before).