I am sorry, this is abolutely forbidden. If you rent your E-AB, the plane is carrying someone (the pilot) for hire. Ask any FSDO. This is exactly why there is such a production over LODAs and transition training.
If you own the airplane, you may hire a cfi, no issues. Or if your spouse does not charge you(!), that is okay. It is charging for the airplane that is the issue.
Whether or not it is a good idea to be your spouse's cfi varies, I think, from couple to couple. How well does he or she respond to criticism?
Ken is correct, designated examiners are allowed to decline flying in E-AB aircraft. However, around here, it is easy to find some who will, especially RVs.