I do notice it on zooming the MP sales pic https://marketplace.secondlife.com/p/T-R-O-Y-B-R-O-N-Z-E/5968924 if someone else might have a tip and wants to look) enough that I´d have tried the offered demo before buying. Strange, are there men who´d want that on purpose or why is it even made that way?
There are eyebrow removal tattoos, at least for female skins (example: https://marketplace.secondlife.com/p/unBra-DEMO-Eyebrow-Removal-Mirage/5386272 ) so in theory you could use an eyebrow removal tattoo and plaster another eybrow tattoo over it (found one for men even: https://marketplace.secondlife.com/p/Tintable-Masculine-Eyebrows/1937200 ) , but you´d need a (nearly) perfect match to that skin then of course with the remover tattoo or it might be a case of the cure is worse than the poison
You say you have the TMP mesh body, that wouldn´t make a difference really unless you use the TMP mesh *head* too? Then you are stuck with what appliers are provided with their HUD or made expressly for that mesh head regarding add-ons or make-up I think.
Else...maybe a haircut that hides the 'problem area'?