Just a couple of for sure openings in a public league:
AL East:
https://www.whatifsports.com/HBD/Pages/Popups/FranchiseHistory.aspx?fid=1485
NL South:
https://www.whatifsports.com/HBD/Pages/Popups/FranchiseHistory.aspx?fid=1494
Always great to get in the season before as a replacement so you can have a bit more budgeting and can resign the free agents.
As this is a replacement gig- PM me, and you must have 3 seasons experience and not be a current replacement owner (WIS rules, not mine or the league's)