The kof counterparts of Terry, Mai and Geese (lesser degree then other two), have huge buffs to them, the latest kof title for Mai episode kof13 in 2010, meanwhile Death Battle had that fight in early days
Although i dont remember if they included kof on the first two or not precisely, but if they did...well they are tier 2 as of right now
For Geese, as of right now, he scales above in AP by like hundreds of times, along speed by like a x1.21 in difference against base Heihachi, but loses to full power by a huge margin that is one shot blitz
On top of not being as haxed in comparison or having ways around Heihachi stuff at all:
-ki attacks can be nulled by him and even utilize it for dura neg like Kazuya to harm organs
-has better electricity in combarison and do what Geese can and more, on top of resisting his
-has fire manip too and can resist his too along heat resistance as well
-can null physical blows and use vibrations to make Geese lose balance, launch him airborn from the ground either standing or laid down
Depending how you wanna see skill and experience, Heihachi has 32 years ahead of Geese in age and fought ki projectile users like Akuma, Heihachi fought individuals versed in more styles or characters who beaten these, Jin, Ogre, etc
All of this is based on info available at the time of the episode also