Successfully mutating a creature in play does not make it a new creature entering the battlefield, even if you just turned a 1/1 token into a 6/6 flying trampler
Q3783 Jun
The new cards, all three of which have both standard and rarer, alternate art versions, will release as part of the upcoming D&D / MTG crossover set Adventures in the Forgotten Realms, due out later in 2021
The Card Rotation Mechanic Makes it Easier to Jump On and Off Pokemon Most trading card games have a rotation
A Jolteon pokemon card, the electric-type eevee evolution with spiky fur, pokemon card coloring page
If you want to negate the effect on field and GY, I suggest making it something like If the equipped monster battles an opponents monster, negate that monsters effects until the end of the turn. This should work just as well in most cases