Is it possible to have Second Skin converted into a sharing buff like Spotter and Vampiric Aura?
Second Skin is meant to enhance the boon on the player having the trait - in technical terms I think it would be a little challenging to even make it work as some sort of 'sharing buff'
There are multiple conditions and factors to take into account in your request - while it would be interesting and add another layer of group utility, I think keeping it a selfish trait is fine - although I wouldn't argue on the fact that while the trait itself is interesting, it sounds more like a minor trait than a major trait.
Soulbeast Feedback >> Dagger Skills / Beast Abilities / Stance Skills
Ye, the idea was meant to be the last on your list.
I don't imagine it would be too difficult to implement either.