If you are on a console (PS4/Xbox) or prefer not to use external software, you can use an in-game exploit to generate funds:
If you are already using (the essential launcher for PES 2021 mods like VirtuaRED or Smoke Patch), you can install Lua scripts that act as a passive money tool. pes 2021 master league money tool
The is not a requirement; it is a liberator. For the purist who loves the grind of taking a League Two team to the Premier League organically, you do not need this. Stay pure. If you are on a console (PS4/Xbox) or
Always back up your Documents\KONAMI\eFootball PES 2021\save\ML00000000 file before starting. making external memory editing impossible.
These money tools only work on the PC version of PES 2021. PlayStation and Xbox versions encrypt save files, making external memory editing impossible.