Combining Players skills to mix with other class skills

Now a lot of people use Chrono and warrior. I only see less Shadow and fixer.
Also some of team need just specific skills like Mana Gate. If the player doesn’t have one they will kick.

So How about Combining Other class skills to make more cooperative and fun.

For example Chrono’s “Fire Wave” and Fixer’s “Heal” combine to generate “Heal Wave”. Wider range of Heal magic.

If such thing possible could be good. However seems difficult to combine skills while playing the game because this is not turn based RPG…