Games like Ace Survivors
Games like Ace Survivors include Vampire Survivors, Bit Blaster XL, Project Wingman, War Thunder, and LUFTRAUSERS. We matched them by the tags players give Ace Survivors on Steam (Bullet Hell, Flight, Difficult, Arcade, and 2.5D): closest matches first, and among equally close ones the better-known games.

Vampire Survivors
Shared: Bullet Hell · 2D · Arcade

Bit Blaster XL
Shared: Bullet Hell · Difficult · Arcade

Project Wingman
Shared: Flight · Action · Arcade

War Thunder
Shared: Flight · Action · Combat

LUFTRAUSERS
Shared: Bullet Hell · Arcade · Action

Exit the Gungeon
Shared: Arcade · Bullet Hell · Action

A Dance of Fire and Ice
Shared: Difficult · Arcade · 2D

Geometry Dash
Shared: Difficult · 2D · Singleplayer

Enter the Gungeon
Shared: Bullet Hell · Difficult · 2D

Cuphead
Shared: Difficult · Bullet Hell · 2D

BALL x PIT
Shared: Bullet Hell · Arcade · Action

Just Shapes & Beats
Shared: Bullet Hell · Difficult · 2D

Orbt XL
Shared: Difficult · Arcade · Controller

Jet Lancer
Shared: Flight · Bullet Hell · Action

Super Hexagon
Shared: Difficult · Arcade · Indie

Megabonk
Shared: Bullet Hell · Action · Survival

Touhou Tenkuushou ~ Hidden Star in Four Seasons.
Shared: Bullet Hell · Difficult · Arcade

ACE COMBAT™ 7: SKIES UNKNOWN
Shared: Flight · Arcade · War

Ultimate Custom Night
Shared: Difficult · Singleplayer · Free to Play

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

Sky Force Reloaded
Shared: Bullet Hell · Arcade · Action

Hollow Knight
Shared: Difficult · 2D · Singleplayer

Windowkill
Shared: Bullet Hell · Arcade · Action

Ikaruga
Shared: Bullet Hell · Arcade · Difficult