@Daraen ahh sorry, as of now, at default guardians are considered as MVP/boss monsters that's why at default it will not show hp bar. But when config for enabling the HP bar for MVP is enabled, guardians will show HP bar as well. There is no way to differentiate guardians as of now, either they're boss or normal monsters.
I have tried to make a pull request:
I don't know if this is the right fix for this, waiting for the other developers say about it.
But I have tested this pull request on my test server and it should work with config:
With config 5, all monsters & MVP will show HP bar except for Emperium and WOE Guardians
and if ever i have missed any monsters (guardians) you could simply add Guardian:true in their modes and do @reloadmobdb