AliExpress has some of the best leverless controllers out there, and it also sells other kinds of controllers that you should check out.
The Haute42 S16 is a small & slim stickless controller with more buttons than usual, and the S13 edition has less buttons.
With the KBHX-01, you get a mini WASD controller available in different colors and can even work on the PS5 with a dongle.
The Haute42 M16 can also be a WASD controller. As for the M13 edition, it has three less buttons than the M16.
The Punk Workshop Leverless U provides a plethora of features, such as slimness, many layouts, different colors, and custom art.
The T series of Haute42 controllers comes in 16 or 13 button versions to suit your fighting game preferences.
The G series of Haute42 controllers can come in 16, 13, or 12 button editions in order to cater to your needs.
The PXN-008 is a sibling of the PXN-X8. It is made of ABS for the purposes of durability and being waterproof & resistant to fading.
Perhaps the most interesting aspect about the Sunga G1 stickless controller is that it has five more buttons than what we are used to.