I have been trying to find a magnifying mirror that works for me for travel for quite a while. Its been such an aggravation that on my last few trips, I've mostly gone sans makeup.
Well, I wish I would have thought of this, a game changer. There are reading glasses with one lens that can be flipped from side to side depending on the eye you'd like to apply make up (or put in a contact lens)
https://www.ihearteyewear.com/collections/womens-readers/type_makeup-reader
I saw them on the NBC morning show and got them for about half price (about $12 plus shipping). They do carry "regular" readers for women and men and also for computer use and sunglasses.