I don't know. Might be Retroarch. It worked fine on Citra (switch retroarch core). The size being the same is normal. Try seeing if you can run literally any other 3DS game.
@Stealphie
Out of all the games i have, only one runs which i downloaded as decrypted originally
Rest all give me the error i sent after using decryption tool or won't even run.
Should i run over OpenGL or D3d? or wouldn't make any difference?