Is it okay to give a major update to your rhg character (like giving new story,new form,new weapon,etc) when you still battling with someone ?

Yes it is, but you cannot blame your opponent for not using the new update in their current work.

Seems pretty legit maybe some people could do that instead of changing rhg's

Quote from Hsaki

Seems pretty legit maybe some people could do that instead of changing rhg's

http://forums.stickpage.com/showthread.php?50131-Guitarii been there.
You can actually, but I think while in the battle you should use your previous RHG's data before your major update.

Quote from Rosie

Yes it is, but you cannot blame your opponent for not using the new update in their current work.

It's okay for me if they don't use the new update

Quote from Hsaki

Seems pretty legit maybe some people could do that instead of changing rhg's

Yeah, I'm agree with you. Since you can update it with a whole new story, why change it ?