Serebii (Unofficial) (@serebii)

Serebii Update: New Abilities have been revealed for Mega Evolved Pokémon in Pokémon Champions

Mega Meganium gets a new one called Mega Solar which sets Sunlight when a move is used
Mega Emboar gets Mold Breaker
Mega Feraligatr gets Dragon Skin - Turns Normal-type moves into Dragon-type