When I try to run my SDL2 game from the “Ports” folder. It shows a black screen and then goes back to frontend. If ran from SSH, the game launches but button presses goes to frontend and the frontend appears in parts like a glitched image.
In that case, I would definitely talk to the portmaster discord, they have tips for getting things to run on these devices. You can also look at one of their ready to run ports for a sample of how to setup the environment to run your application.
Also, you are running muOS on an Anbernic, correct?