Outside of some other bands that other users have already mentioned, one band I’m aware of is a Swedish metal band called All Ends. It’s been a while since I’ve listened to them but I know about them because the lead singer worked with Crush 40 for the final boss theme from Sonic and the Black Knight.

There are some other bands that I’m going to mention but they don’t exclusively make metal (or at least I think, I haven’t heard all of their music yet). And yes, they are all bands who make remixes of music from the Touhou games, which their is probably more artists I could mention but I have either forgotten them or just haven’t listened to them yet.

The Other Flower, I almost forgot about this artist, Karma is great example of their music.

Akatsuki Records, Bloody Devotion is a great example of their music.

Undead Corporation, The Dream Of A Rabbit Singing In The Night is a good example of their music but I know that they do have music that is much “heavier”.

Get In The Ring, while the title says it’s “rock” despite the fact that it’s clearly metal, 祭炎 is a good example of their music.

Sound Holic, because I don’t use Spotify anymore, I have forgotten what the best example would be. The song I’ve been listening to the most that is at least partially metal is Grip & Break down.

A-One, while I know that they are primarily a eurobeat artist, they often mix other genres into their music. An example of a song that mixes metal with eurobeat is God Only knows, which is from Initial D the Arcade (2021).

There is one more that I want to mention but I don’t know if the example I have is “heavy” enough to be considered metal or if it’s just “orchestral rock”. It’s 蒼月の懺悔詩～Universal Nemesis by Yonder Voice. They might have heavier but as I stated earlier, I haven’t heard all of their music yet.