Soul Drinkers come to mind. They are Renegades but still loyal to the Imperium. Knights of Blood as well.
There's a few others where it isn't so clear.
Seems when most Space Marine Chapters turn Renegade it's generally due to the Inquisition fucking them over despite the majority of the time them doing nothing wrong. Which makes it seem like it's only a matter of time before the Inquisition gets ahead of itself and takes the full wrath of a Space Marine Founding Legion
Grayson Thompson
I think we all know what the best race is.
Carter Sanders
Of course
Caleb Williams
The Speesh Wolves had a full blown war with the the Inquisition after Armageddon and other chapters like the Dark Angels and their sucessors, the Blood Angels and their sucessors and a bunch of others have a habit of making nosy Inquisitors disappear.
Henry Smith
How long till the Inquisition get an Imperial Fisting? :^)
Justin Jackson
Can't wait to see Cyber-Gabe rip and tear in DoW3
Carter Jackson
The only good tau is a dad tau.
Brayden Phillips
Imagine what an Ork computer would be like
It would have like 3 buttons and would still somehow type whatever message they want as they smash it repeatedly