If you just want without a tool: Use a Cheat Engine scan (initial value → spend some GP → scan decreased value). Takes 2 minutes and works with any PES 2021 version.
: Open PES 2021, then open Cheat Engine and select the game process. Navigate to Negotiations pes 2021 master league money tool upd
: Sign young, 16-year-old players for low wages and trade them to other clubs for their lowest-rated players plus cash, or release the received players to clear space. If you just want without a tool: Use