With the disclaimer that I am not particularly skilled in make-up and prosthetics, my suggestion is that you conceptually divide the eyebrow up into two roughly equal pieces. The first part is the part that you will punch individually along the lower half inch or so of the headpiece, where you will attach it with spirit gum/Pros-Aid/superglue/whatever to your forehead along the brow bone.
The second part would consist of hairs made from the same material. They would be attached to the bottom of your natural brow line
*after* you have attached your headpiece. Once the adhesive has dried, use a comb with a very thin, tapered end (like a rat tail comb, but smaller) to blend the hairs attached to your skin upward into the hairs punched into the bottom of the headpiece, then set with fixative. As long as both the headpiece and the brow hairs immediately below it are securely attached
, this should serve to blend your eyebrow hairs into a natural look and help to conceal the “seam” where the prosthetic meets your skin.
It will also help with any hair-related endeavor if you can vary and mix the colors slightly, and use a higher concentration of the lighter colored hairs along the hairline.
I hope that is of some help; my knowledge of the terminology involved is weak. If your goal is a realistic, natural look, I don’t see any alternative to the time-intensive task of punching/sewing and applying each hair individually, or 2-3 at a time if you have good coordination and a very good eye. Anything else and you will look like the surgeon did a poor job installing your hairplugs.
As for glue holding.... I have yet to find any sort of non-toxic adhesive that will hold anything in place for any length of time. Either it’s not strong enough or I sweat it off (though coating the bare skin with something like Mehron barrier spray fixative
may help with the latter and buy you some time).
I hope you find something useful in there somewhere. As always, be sure to experiment with scraps before attempting *any* procedure on your work-in-progress! Will you let us know how your project succeeds (or doesn't), so that others may learn from your experience?
Wishing you Qapla'!*