Hello captn_pete / welcome to FEU!
Just in case you didn’t know there are repositories with free-to-use graphics resources available (in graphics repo, its google drive(here), or by searching “mug blitz” from the search bar). You can use assets from those sources in your projects as long as credit is given.
Battle sprites take lots of time to make so please find one from the repo or make a very good case for one being made. You need to structure your request very concretely (“I need X design using Y weapon-types”), the more references you have the better, including a proof of concept/projectPatch, being willing to assist with scripting/understanding the process, all help in making your animation request more acheivable and likely to be taken.
As general ettiquette, please don’t use things you “find” without being sure the creator is okay with you using them.
If you do have permission to use the mug, its colors suffered from compression and frame misalignment, to some extent I’ve cleaned it up for you. Make sure when you’re working you keep your image within 16 colors and save in a lossless format. (Feel free to ask questions here or in the FEU discord if you’re feeling lost.)
Splices are pretty simple to learn and the formatting is very important for importing into GBA so I’d recommend you give it a try so you can get a feel of the fundamentals. I’ve arranged some willing canidates for splicing a hood onto the Mark mug.
If you’ve reached this point, thanks for wading through all that, good luck, and happy hacking!