Energy » Fusion Strike Energy | Abilities » Poison Peak
Does a poisoned Fusion Strike Pokemon with Fusion Strike Energy attached take additional damage counters from Radiant Hisuian Sneasler's "Poison Peak" Ability?
No, because Poison Peak is an Ability and Fusion Strike Energy prevents all effects of your opponent's Pokemon's Abilities.
Source: TPCi Rules Team (2022-09-29)
Abilities » Hazard Star | Abilities » Poison Peak
If I use Drapion VSTAR's "Hazard Star" VSTAR Ability to poison my opponent's Pokemon with 3 damage counters during Pokemon Checkup, and I have Radiant Hisuian Sneasler with the "Poison Peak" Ability in play, does my opponent put 3 or 5 damage counters on their poisoned Pokemon during checkup?
Five damage counters. Poison Peak adds 2 damage counters to whatever the current number of damage counters are being placed for poison.
Source: Lost Origin FAQ; TPCi Rules Team (2022-09-08)