Games like Gunvein
Games like Gunvein include Bit Blaster XL, Nova Drift, Planes, Bullets and Vodka, BALL x PIT, and Ikaruga. We matched them by the tags players give Gunvein on Steam (Shoot 'Em Up, Action, Bullet Hell, Arcade, and 2D): closest matches first, and among equally close ones the better-known games.

Bit Blaster XL
Shared: Shoot 'Em Up · Bullet Hell · Arcade

Nova Drift
Shared: Shoot 'Em Up · Bullet Hell · Arcade

Planes, Bullets and Vodka
Shared: Action · Shoot 'Em Up · Bullet Hell

BALL x PIT
Shared: Action · Bullet Hell · Arcade

Ikaruga
Shared: Shoot 'Em Up · Bullet Hell · Arcade

LUFTRAUSERS
Shared: Bullet Hell · Action · Arcade

DRAINUS
Shared: Shoot 'Em Up · Action · Shooter

Mushihimesama
Shared: Shoot 'Em Up · Bullet Hell · Action

Vampire Survivors
Shared: Bullet Hell · 2D · Action

Revolution Ace
Shared: Shoot 'Em Up · Action · Bullet Hell

Star Saviors
Shared: Shoot 'Em Up · Action · Bullet Hell

DoDonPachi Resurrection
Shared: Shoot 'Em Up · Bullet Hell · Arcade

ZeroRanger
Shared: Shoot 'Em Up · Bullet Hell · Action

Dimension Tripper Neptune: TOP NEP
Shared: Action · Arcade · Shoot 'Em Up

Sky Force Reloaded
Shared: Shoot 'Em Up · Bullet Hell · Arcade

Touhou Koumakyou: New Classic - the Embodiment of Scarlet Devil
Shared: Shoot 'Em Up · Bullet Hell · Action

Super Bit Blaster XL
Shared: Shoot 'Em Up · Bullet Hell · Arcade

Touhou Kouryudou ~ Unconnected Marketeers.
Shared: Shoot 'Em Up · Bullet Hell · Action

Touhou Kinjoukyou ~ Fossilized Wonders.
Shared: Shoot 'Em Up · Bullet Hell · Action

Space Invaders Extreme
Shared: Shoot 'Em Up · Bullet Hell · Action

Crimzon Clover World EXplosion
Shared: Shoot 'Em Up · Action · Bullet Hell

Beat Hazard
Shared: Shoot 'Em Up · Bullet Hell · 2D

METAL SLUG
Shared: Action · Arcade · Shoot 'Em Up

Touhou Juuouen 〜 Unfinished Dream of All Living Ghost.
Shared: Shoot 'Em Up · Action · Bullet Hell