Is bioidentical progesterone topical cream for arms just as good as taking a 50 mg bioidentical capsule at night before bed for menopause hot flashes?

Neither. The term "bioidentical" is a marketing tool, used to make people believe that these products are somehow better or safer than other forms of hormones. There is no good evidence that this is true. Most topical creams are not regulated by the fda, and so their effectiveness is mostly unknown. Estrogen is the much more effective hormone for treating menopausal symptoms than progesterone.