I was testing this for about a week via cbhc and homebrew launcher auto boot (auto boots into dark mode without pushing any buttons with special version of plugin loader). I saved the plugin loader in another folder on the sd card. anyway, there were a few issues that made me change back to normal wii u mode.
first, dkc tropical freeze wouldn't start with the A button unless you pressed the home menu, then resume. the only other game I tried was 3d world, which doesn't have this problem, so tropical freeze must do something with the home menu at start.
the other thing is that the usb loader gx forwarder on the wii u menu would no longer work, because I think it's a hbl to hbc forwarder. it would result in a black screen. anyway, I reverted everything back, and tropical freeze now works without that A issue, and the usb loader gx forwarder works again. I think tropical freeze's problem is related to dark mode, and usb loader gx's is related to the homebrew launcher.