• The King of Fighters 2002 - Fans will argue over whether 98 or 2002 is best. 98 does not have Kula in it, so 2002 is better.

• Puzzle Bobble - If you have a friend to play with, the original is still the best. However, there's no versus CPU, so substitute Bobble 3 if you're playing by yourself.

• Waku Waku 7 - Incredibly goofy and colorful fighting game, every single character is a parody of 90s anime/game tropes.

• Twinkle Star Sprites - A versus shmup with a super unique format.

• Windjammers - A sort of extreme pong.

Also check out FightCade for netplay, many of these games have active communities.

Puzzle Bobble. I had the cabinet gifted from my boss 25 years ago. Very addictive game.

Used to convert Neo Geo's to MAME cabinets for Amsterdam coffeeshops.

Really depends on what genres you like, but here are some non-one-on-one fighting games I haven't seen mentioned:

Blue's Journey

Neo Bomberman

Neo Mr. Do!

ZuPaPa!

Nightmare in the Dark

Ganryu

Burning Fight

Mutation Nation

Robo Army

Spin Master

Bang Bang Busters

And an honorable mention; it's a on-on-one fighter, but it's fun to see SNK's take on Capcom's characters:

SNK vs. Capcom

The following game choices are objectively correct from a long time Neo Geo nerd. What anyone else tells you is wrong. (I kid, I kid. Mostly.)

• Twiklestar Sprites
• Samurai Shodown 3 specifically
• The Last Blade (not its sequel)
• Twinklestar Sprites
• Money Puzzle Exchanger, but only its attract screen
• Viewpoint
• Twinklestar Sprites
• Blazing Star
• Waku Waku 7 (and to a lesser extent its predecessor, Galaxy Fight)
• Aero Fighters 2
• and lastly, Twinklestar Sprites

If you're going to play KoF or Metal Slug anyway, the best King of Fighters is '99, and the best Metal Slug is 2.

Samurai Showdown is a decent fighter

Played up to Metal Slug 5 from the franchise (incl. Metal Slug X), and all were pretty good, specially if playing with a friend. Also all of those you can find digitally officially nowadays.

Other than those, only played The King of Fighters 2002, which was fine.

Windjammers KOF '98 Neo Drift Out

I've been playing some Neo Geo recently too :D

Neo Geo:

• Crossed Swords
• Far East of Eden - Kabuki Klash
• Garou - Mark of the Wolves
• Magician Lord
• Sengoku 2
• The Last Blade
• Top Hunter: Roddy & Cathy
• Twinkle Star Sprites

Off course there are much more fighting games, but I didn't want to spam them here.

Edit: Replaced a game in the list.

Neo Turf Masters - one of the best gold games made!

Metal Slug

Sengoku 3

Super Baseball 2020

Double Dragon

NAM 1975

Marvel vs Capcom