This is a very broad question that would be difficult to answer definitively. So little commercial software was released for CP/M 68K and it was largely abandoned by both its users and Digital Research. 68K enthusiasts preferred OS-9, Unix, or bought a Mac, Amiga, or Atari ST. Heck even the KaOS operating system was probably more successful.
As a result CP/M 68K really only shipped with a handful of expensive systems as an option (SAGE, etc.)
Of the commercial binaries I can find on the net and from memory none took more than ~300K. Binary size is not even a good indicator of memory usage, for example the Binary size of Pascal for CP/M 68K is 250K but it only requires 128K to run. It must use overlays.
Maybe someone wrote some CAD software for the SAGE or similar that eats up more TPA than 300K, but my instinct tells me 640K would be memory than anyone would ever need for CP/M 68K.