Some mogs are armor type specific, others are just cosmetic appearances. The cosmetic ones can be used providing a character has reached renown 80 for each relevant covenant. This can be on one character or multiple.
Back in the day I did each renown 80 on four characters initially but you can do it all on one, my main later did just that. But it’s the renown 80 that unlocks it for alts.
I was Kyrian and mogged into all my Venthyr stuff, I preferred their aesthetic. I still use it to this day. I’m technically a Night Fae to collect the soulshapes and still happily mogged into my Venthyr cosmetics
Yes your rogue will be able to use any suitable sets without setting foot in SL providing they’ve been unlocked by other chars.
Thanks for the information .
So basically I can farm renown 80 on one char (the DK in this case) and after my alts that use different types of armor will have access to it.