Games like ButtonMash
Games like ButtonMash include Banana, Brawlhalla, Himno, Pikuniku, and SANABI. We matched them by the tags players give ButtonMash on Steam (Adventure, Casual, Platformer, 2D Platformer, and 2D): closest matches first, and among equally close ones the better-known games.

Banana
Shared: Casual · Free to Play · 2D

Brawlhalla
Shared: Free to Play · Casual · 2D Platformer

Himno
Shared: Platformer · Adventure · Free to Play

Pikuniku
Shared: Adventure · Casual · Indie

SANABI
Shared: Adventure · 2D Platformer · 2D

Celeste
Shared: Platformer · 2D Platformer · Indie

The Darkest Tales — Into the Nightmare
Shared: Adventure · Platformer · Free to Play

Slime Rancher
Shared: Adventure · Cute · Casual

Thank Goodness You're Here!
Shared: Adventure · Casual · 2D Platformer

Hollow Knight
Shared: Platformer · 2D · Adventure

Laughing to Die
Shared: Adventure · Casual · Platformer

Helltaker
Shared: Free to Play · Cute · Indie

Bongo Cat
Shared: Free to Play · Casual · Cute

Sonic Superstars
Shared: Platformer · Adventure · 2D Platformer

Webbed
Shared: 2D Platformer · Platformer · Cute

Janosik
Shared: Adventure · Platformer · Casual

BEEP
Shared: Adventure · Platformer · Indie

Neva
Shared: Adventure · Platformer · Indie

There Is No Game: Jam Edition 2015
Shared: Casual · Adventure · Free to Play

GRIS
Shared: Adventure · Indie · Platformer

Idle Champions of the Forgotten Realms
Shared: Adventure · Free to Play · Casual

Hollow Knight: Silksong
Shared: Indie · 2D · Platformer

Pizza Tower
Shared: 2D Platformer · Platformer · Indie

Florence
Shared: Casual · Adventure · Indie