I want to install a mirror on the wall between the bathroom and the bedroom door, can I?

This is not recommended. The placement of mirrors in Feng Shui is very particular. Geomantic omen says that mirrors are fragile and attract ghosts. It is best to put one or two mirrors at home.

In Feng Shui, the mirror is also an evil. If you put it away, it is a kind of mascot. If it is not properly placed, it will form an evil spirit and have a certain impact on the family. What you said is even more undesirable. No matter how the house faces the water, the placement of the mirror should be hidden. In geomantic omen, mirrors can reflect good luck and attract evil spirits into the house.

I suggest you put the mirror in the closet or install a mirror on the bathroom cabinet. Mirrors are not recommended elsewhere.