(a) An agreement to convert separate property to community property:
(1) must be in writing and:
(A) be signed by the spouses;
(B) identify the property being converted; and
(C) specify that the property is being converted to the spouses' community property; and
(2) is enforceable without consideration.
(b) The mere transfer of a spouse's separate property to the name of the other spouse or to the name of both spouses is not sufficient to convert the property to community property under this subchapter.