Try Casiopea, the Mint Jams album. Saw it in a green text. It's what made me fall in love with the genre.

I've been a listener of all types of jazz for about 15 years. In my experience, Japanese jazz is akin to having one of those YouTube 'chillhop lofi Jazz' live streams up. It isn't super technical and gets a bit repetitive to me, but it's nice to have on every now and then while I'm trying to multitask.

as OP said, Casiopea's Mint Jams is a bomb, I also suggest these albums I really enjoyed:

• Himiko Kikuchi - Don't Be Stupid
• Hiroshi Suzuki - Cat
• Masaru Imada - Green Caterpillar

There's a lot of great Japanese jazz from the 70s and early 80s. Check out Kazumi Watanabe, from his early guitar-oriented days to the more full instrumentation of his compositions in the 80s and 90s. A favorite of mine is To-Chi-Ka, which also features Marcus Miller on bass. There are also a lot of great albums with female vocalists such as this one by Noriko Miyamoto and Isao Suzuki.

Look up T Square. Shit’s amazing

https://youtu.be/CT5rwLr0yFo?feature=shared

https://youtu.be/uwAFE0zLPgo?si=O53ebSaprHgv889H

Dunno if this counts, but this is a pretty dope jazzy instrumental Japanese band that I love!

Ocean Drive - Katsumi Horii Project (1988)

Technically "jazz fusion", but it still slaps

Seba Jun