NSUI does that. It creates gba vc injects. The only thing is it still uses the gba mode which the 3ds needs to boot to. Otherwise you will need to create gba forwarder vc injects. which would use a emulator like mgba.
You find a bounty site that offers 3ds programs to be made. and be ready to have a few hundred / 1 - 2 thousand dollars ready to be paid as this is a rather poor rated game with better same genre titles out there
Do you have the source code for the game? ports are not just a copy paste like most people tend to think. If it was easy in any way there would be 100s of poorly ported games on the 3ds.
If the saves are made using a gateway. then it will need gateway to decrypt them. checkpoint and jksm both do a good job decrypting saves outside of if a gateway was used