Grass is the only major effect to not return in future games. No known attacks in Super Smash Bros. 4 or Super Smash Bros. Ultimate use it; despite Ivysaur being present in the latter, its attacks are generally Normal. It is unknown whether the effect is merely unused, or removed outright.
The Subspace Emissary
In The Subspace Emissary, almost all enemies have the same resistance to both slash and grass attacks; Primids are the only exception, taking 1.3× damage from slash attacks but 1.0× from grass attacks.
List of grass attacks by characters