Other than the gains Dolson has already made in transforming her body, I think this is an unusual year in that conditioning won't be as big of a factor.
Besides Stef, the only two people who stand to play more than 20 mins/game on this team are already highly-conditioned, experienced players capable of going the full 40 mins: Bria and Kelly. I think we will see a heavy rotation at forward with Stewart and Tuck (sometimes Kelly), with Breanna possibly going 20+ mins as we get deeper into the season. (She seems like she is easily well-conditioned enough to give 20 quality minutes for Geno already.) We will also have a lot of rotation at the point with Caroline not likely to exceed 20 mins.
This leaves KML who, depending on her performance, could see 20-25 mins per game. She's saying all the right things and it appears she is mentally tougher this year, which is 1/2 the conditioning battle. And she progressed steadily last year when it came to maintaining intensity on the court. Geno was hard on her but he's especially tough on those with 1st-team AA talent. There were times she was sucking wind out there but not that many as the season wore on. I think conditioning will not be a big factor for her this year at 20-25 mins/game.
Barring injury, the rest of the players coming off the bench--Banks, Jefferson, Buck, and Stokes--will likely hit 20 mins only when it's a 2nd-half blowout, and at that point there is no real impact to the outcome if there were to get gassed and need a break.