Some personal favourites are:

Wayang Kulit - Abyss of Time (TEKKEN TAG TOURANMENT 2)

Mystical Forest (TEKKEN 6)

High Roller's Club (TEKKEN 6)

And last but not least, the classic - Sparking! (TEKKEN 5)

The series has experienced a lot of style shifts in its OST over the decades, but a lot of the older soundtracks are still bangers.

This has helped me out a million times when trying to mess around with a new character and it's helpful to have on the side - HIGHLY recommended for new players!

ultramarineandwhite: has several pieces featuring Lars, Claudio, Alisa and some other Tekken chars.

lag: IMO, one of the coolest new artists I've found, posts art of every char and one of his panels is even in the game now! (For Law players)

gdaigonΛЯT: Frequently draws several different Tekken chars.

Jasmin Darnell: Not specifically a Tekken artist, but she is the costume designer of Lili in Tekken 8.

hungry_clicker: general FGC content, sometimes Tekken related.

Hanny: more of a general artist now, but still occasionally draws great Tekken content.

Do you have any others you particularly like? I'm looking for more to follow too, let me know.

All credits for this go to @joeytcb989 on YouTube.

Wavu wiki is a fantastic project with a ton of contributors, they have a discord server here. Some pages might seem empty/unfinished - but if you think you can improve it, your help would be appreciated - otherwise, it's still a good resource to learn the game.