Anomandaris

Brandon has stated that there is some sort of set conversion between Breath and Stormlight when asked about a certain character, but he either hadn't actually set the amounts yet or couldn't recall the ratio off the top of his head.

hoid doesnt glow like ealatrin so he doesnt have that I think

Well Vasher is able to suppress his Returned aura, perhaps Elantrians just haven't figured out that particular trick, or maybe Hoid is just far enough away.

On the other hand, I'd be kinda surprised if he actually was Elantrian, but perhaps there is a way to acquire some of their powers in the same way that you can use Lerasium or be an Awakener/5th Heightening without being Returned.