Please note that the following answer only applies to clients residing in Germany.
Yes, loss pots are generally transferred, but only in the case of a complete depot transfer to Scalable Capital. The depot transfer from the other broker to Scalable Capital can be requested in the Scalable App.
There is one exception: You maintain ongoing business relationships with Baader Bank outside of Scalable. In this case, your loss pots remain with Baader Bank.