Dash has a cooldown! So cooldowns are in fact in this game + we know that the devs are capable of it!
~~Balancing~~
They could probably have it added to certain charge attacks.
Take any weapon that is considered overpowered by its charge attack, and place a short cooldown on charging it.
~~Making charge attacks more meaningful rather than necessary / spammed~~
Personally, what I would do, is make charge attacks not a necessity to certain weapons. Chaining charge attacks with brandishes etc is something that doesn't require much skill as opposed to normal attacks with many weapons, but it just makes sense to chain charge attacks since charge attacks are powerful enough + you are only in the fray for a moment. Sword users should up in their faces using normal attacks more.
Instead, I would place a universal one, two, or three minute cooldown on ALL charge attacks except for bombs (bombs are completely unaffected), and buff all charge attack damage accordingly (brandishes won't receive much, Blitz Needle won't receive much, heavy swords will receive a lot, Calibur / FoV will receive a fair amount, Gran Faust should receive a bunch imo, etc etc etc)
People will dislike this idea since it's new and anything that is new is shunned, but think of it. Weaving normal attacks requires more skill + how fun it would be to launch a charge attack that was absolutely meaningful. "Oh, they're already meaningful" Oh, you're boring. 100% damage increase to initial hits / some explosions =/= exhilirating by any means. Plus normal attacks take more skill.
+1