Recently I have given up wearing makeup as I now know that it is not allowed.
I have a lot of makeup I wish to remove from my home.
Is it okay to give this away to Muslim family members that wear makeup?

Makeup to be worn infront of Na mahram is forbidden and attracting them would be counted as a sin. You can keep it and use it appropriately for your spouse or other gatherings where women usually attend, there is no harm in that, rather, it can be an act of virtue if done for the sake of Allah's pleasure.
If you still want to distribute it, do so to people whom you know would not use it in the wrong way as I've mentioned, ie, attracting Na mahram.