Maybe this Tutorial can give you some help:What I need to play DS games on Gateway Blue Card? I have O3DS+a9lh+luma3ds.
Last time I played a DS game, I had a Nintendo DS and a AceKard2... Good times.
I saw this in some kinda old post, "Part 1: To use the Gateway Blue card we need an unpatched TWL_FIRM, otherwise it interferes with the patches Luma3DS uses."
I really need to do this? Beacause Idk what exactly is TWL_FIRM
https://gbatemp.net/threads/tutorial-using-luma3ds-with-gateway-on-v2-a9lh.431691/
Or maybe this: https://gbatemp.net/threads/list-of-all-gateway-questions-9-2-0-20.375142/