It's easy to assume it could eventually happen, but there's also the fact that Larian never released an expansion for any of their past titles so far.
That aside, at this point in time and with all the work left to do on the base game, I'm not sure if even they could answer the question with any degree of confidence.

Party control in Baldur's Gate 3 is a complete mess that begs to be addressed. SAY NO TO THE TOILET CHAIN