Some people have great luck using a red or orange lipstick under their foundation to cancel out the "blue black" of their beard. One dabs on the lipstick lightly and sets it with powder. The next thing is to put foundation over that. Having said all of that, it never worked for me

What has worked over the years is the beard cover that TV (excuse the pun) anchors use. It is available in costume shops. You put it on over the shadow, powder it and then put foundation over that. You have to go lightly or it will look like it was caked on. I have also used Dermablend, which is sold in many stores. It is used to cover scars, tatoos etc. It also is very heavy, so care is essential. The trouble I had was it didn't really match my skin tone and it only comes in a few colors.
The best advise I can give is like Julie's, go to Clinque, Merle Norman (my favorite), Mac (very trans friendly and trained to help us, I'm told) or to a Mary Kay Lady. They should be able to help you. Good luck, I love makeup and I hope you will, too!