by AlanLC

Link: https://gbatemp.net/threads/nes-snes-oline-custom-overlay.583905/

sysmain.scn:
romfs/bootapp/resources/scenes/sys/sysmain.scn

Change “Layer”: 0 To “Layer”: 1
Change “Size”: [2048, 1280] To “Size”: [1920,1080]
Change “uvRepeat”: [2,20] To “uvRepeat”: [1,1]

Overlay:
romfs/bootapp/resources/sprites/colorhalftone.png