Vulpes
Scholar
There is no automatic regeneration or regrowth of lost limbs for thin-bloods and something like branding would be treated as an Aggravated injury, which is a lot harder to recover from for both them and normal vampires. There's also no need to constantly re-brand them when there are already dime a dozen level 1 rituals that can permanently alter someone's appearance, such as:How can you permanently mark thinbloods when vampires regenerate all their wounds and always revert to their original appearance, sooner or later?
Is there a designated Camarilla brander who regularly checks up on all the thinbloods to see if they need to be rebranded?
Brand - makes scars, burns, tattoos and any other changes to the flesh permanent (renamed to Seal the Brand in V5)
Beat your Way to Glory - beat the superficial characteristics out of someone and onto you (this is what V20 Anarch Sorcery is like BTW)
Rebirth of Mortal Vanity - lengthens your hair
Purity of Blood - expels foreign materials like piercings, tattoos, hair dye, etc.
And before anyone tries to come back with the "B-B-BUT ONLY TREMERE CAN DO BLOOD MAGIC!!!" cope, that's false as anyone can learn blood sorcery and about a third of the clans already have access to it. What makes the Tremere unique is that they have a much easier time learning the Paths and rituals belonging to other clans.