Hatter’s special ability:
“Steals all dispellable buffs from all enemies and randomly casts them on all allies.”
Malosi’s special ability:
“The target cannot cast any new status effects or stacks on enemies or allies for 3 turns.”
I hit the Hatter with Malosi, effect was applied. Hatter then used his special and stole buff gained from Poseidon and his allies gained the buff.
Based on the wording that last part should not have happened. Either this is a bug or the in-game wording is not correct.
Unfortunately I have no screencap or video but this should be easily reproducable.