Highkeep and Rogue epic
 

Was wondering if I killed highkeep guards would i still be able to do the rogue epic later on? Thanks!

The guards are on different faction than Stanos I'd imagine. What are you worried about in particular?

You'll be fine as long as you complete you're epic BEFORE chain killing Stanos for his head (High Elf Illusion mask).

You can do sneak hand in on Stanos to get your epic, regardless of faction.