The Granola Summit is an open source PLA Pro controller that has a port for additional console compatibility.
The KBGM-H04 is a dual layout controller with an aluminum alloy top and acrylic bottom. You can also add an extender for your wrists.
The Leme Tech One is a Smash controller that runs on the proprietary Leme Tech One firmware, which is HayBox-based and HayBox-compatible.
The DuelPad A16 is an acrylic controller that has 16 buttons with LED support and even comes with a modern console port.
The Ruyi Box is a stickless controller with 18 face buttons curved quite interestingly as well as two analog sticks.
The button layout of the Meisterboard from Bavaria is supposed to make it the most ergonomic fighting game controller.
Cubs made a hybrid, the Cubstraption, that has a GameCube controller on the left and half of a box controller on the right.
The ST is a primarily stickless controller that is made of inox steel, has a see-through bottom panel, and glows in different colors.