The Brewers generally don't let assets expire. They'll likely sell the players who for sure are going to be a free agent (Civale, Cortes if he gets healthy in time). If Hoskins keeps up an .850 OPS pace he will for sure decline his 2026 option and thus the Brewers will likely sell on him. Quintana probably given his age risk, although he would likely accept his 2026 option because one year and $15M is about as good as he will do as a FA at his age.
They have the SP depth to sell off Civale, Cortes, and Quintana (Peralta, Patrick, Henderson, Priester, Woodruff, Myers, Rodriguez, maybe Mis depending on his innings limit for this year) even if they are in contention for a playoff spot. If in contention, they could flip Civale or Cortes for a 1B if they trade Hoskins.