In the island there are:
4 Tontatas devil fruit
1 marine devil fruit
2 strawhats devil fruits
3 strawhats off island allies with devil fruits
1 royal family devil fruit
2 active members of Doflamingo pirates
8 (plus bellamy and baby 5) members of the Df pirates with devil fruits
at least 2 figthers in the tournament with devil fruits (Barto and the jacket fruit guy)
Sabo
Wasp, Beetle, Healing, Sewing
Gravity
Gum, Flower
Disguises, drawings to life, OP
Voyeurism
Strings, flamable mucus
Ton, Swim, Burst, Gyro, Art, Hobby, Stone Asimilation, Flag, Weapons, Springs
Barriers, Jacket
Fire
That is 26 different devil fruits in the island right now. Not counting the smiles, and Brook, Chopper, Caesar and Momonosuke that are already gone, and if you count them, then you have to count the Big Mom ship (wheter is a robot, a devil fruit user, a devil fruit effect, or just a rare animal who wears a ship and talks) and Pekoms (might he be a lion who ate the turtle fruit, a turtle who ate the lion fruit, a minkman, or a half minkman lion half fishman turtle)
I'm guessing that there is little motivation for a devil fruit user to get into a tournament to win a devil fruit, so that's why there shouldn't be much more of those there.
Alabasta had:
2 strawhats
2 royal guard
8 barroque works agents (including mr3)
2 marines (smoker and hina)
and Ace for like an hour
Einess Lobby had:
3 strawhats
6 cp9
Aokiji for like 3 minutes
The war is impossible to count because there are too many unknwon devil fruits there, but I guess that is the only arc that could top this one in the number of devil fruits, and Kaidoh is supposed to top that with the Smiles!