Barkskin is changeling magic, but you only get the vfx when it's cast from druids level 7+ (I believe?) It would be cool if drinking "changeling brews" had the same stigma that druids face all the time now. Barkskin potions/items should give you the bark vfx, and barkskin spells cast by a powerful Druid should give you an extra vfx- a green glow, perhaps.
It's so ugly though....
I'd actually suggest a toggle ability to remove barkskin fx, so the CHANGELING! KOS!!!! is less easy
I don't think people really treat bark as an obvious sign of changeling magic so I don't see the point personally.
Gets a bit muddy if we want people to treat it that way if you happen to be a fungus cleric or an item with a higher level CL of bark as well.
The AC bonus is a bit too integral to the balance of things to make it a highly stigmatized effect as well.
Personally I've seen many, many players call out "Changeling!!!" as soon as they see a barkskin VFX. Both as a druid and before I played a druid.
My understanding is some characters will take visible Barkskin as casus belli, which can plausibly lead to FD, therefore it does lead to FD.
My fellow druids were too scared to cast their Barkskin at all during our struggle to survive. Removing the VFX would perhaps be a kindness to them.
I think if the VFX has to stay or go, it should just be gone. It's such an important tool to have, and there have been situations where people have been subdued over having the barkskin effect.
Although having a way to toggle the effect for those that still wanted the AC would be neat.
The barkskin roleplay is embarrassing and we would be much better off if we removed the visual effect entirely.
Also shame on anyone who subdues people over a visual effect they do not even have control over.