While exploring Discogs, I came across this label,
R135 tracks.
They still exist, but no longer releasing trance. This one from 2011 is pretty nice:
Ryoji Takahashi - Memories in the sand
.
Another one is
Hellhouse Recordings (is it Yoji Biomehanika's label?).
Discogs said it's UK based, but almost all of the releases are by Japanese producers, for example this one:
Shibee - Dawn surely comes
https://soundcloud.com/shibee-yamaguchi%2Fshibee-dawn-surely-coms
There's also Harderground Recordings and Tokio Underground, but I haven't checked them yet.
A friend of mine recommends Diverse System, a multigenre label, but you'll find even more Japanese trance producers there.
This is their trance compilation
.
And the latest, released in 2023
.
If I had to sum up how the Japanese trance sounds are, for now maybe like trance having babies with anime and video game music.