5 After Burner games on 4 systems: Famicom, Master System (US, EU), NES, ZX Spectrum
4 NHL 97 games on 4 systems: Genesis, PC, Playstation, Saturn
The leader, not counting variation is Sonic or Sonic 2 where they are on 5 systems: Genesis, PC, Game Gear, PS2, PS3
But, counting variations it comes out like so
9 Sonic the Hedgehog games on 5 systems
11 Sonic the Hedgehog 2 games on 5 systems
For most variations on one console there are two tied
7 Sonic the Hedgehog 2 games on Sega Genesis
7 PGA Tour Golf II games on Sega Genesis