Its an interesting idea Easy E, but how would you make a diselpunk game more high fantasy?
An interesting thought exercise.
1. The simplest and most straight forward approach is to replace the known Nation-States and Empires of World War I into more mono-race fantasy races.
2. Why would ironclads be useful in a magical world? Perhaps if a certain element/set of glyphs could negate or channel magic differently and therefore provide a protective armor vs. powerful magic attacks. Therefore, ironclads.
3. I could see a system where a ship or fleet had so many Magic resources to distribute around to attacks, defense, automated crew, etc.
4. Fighters could be griffons, dragons, etc.
It would require a bit of world building, but I think it could be done.