Didn't find a post about it and I don't think this is intended.

If you unlock a hidden appearance tint (killing 1000 players or doing 200 dailies), it's unlocked for all your weapons, including those, for which you haven't unlocked the hidden appearance at all.
I think it's supposed to unlock only for those you've collected.

For example, I got my pvp tint using a mistweaver weapon, but can now also use the tint on ww weapon (I haven't unlocked the ww skin at all).

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