Blitz2, Swdtech2, Morph2, etc...

It's certainly possible, but you'll be working with some space constraints. For each extra command (Limit/Bushido/Trance), you'll need an extra command, which means overwriting an existing one. And the same goes for the abilities each new command will use, so that means another 16 or so spells you'll need to find room for - each block of 8 should be consecutive for indexing purposes.

Space in the ROM probably won't be an issue as you can probably just use some free space somewhere, where you'd need to copy/paste the original command code. You'd also need to manually programs the inputs for Bushido if you want them different from Blitz.