Commentary for Kiddushin 135:9

R. Yeshvav laments R. Akiva’s overly strict position. However, it is unclear what R. Yeshvav thinks R. Akiva’s position actually is. If he thinks it is the same as R. Simai does, then we understand how R. Akiva interprets the words “beloved” and “hated.” But if he thinks R. Akiva rules even more strictly, that the offspring of all women prohibited by negative commandments and even those prohibited by positive commandments are mamzerim, then how would R. Akiva understand the verse?
The answer is that R. Akiva could read the verse as referring to a non-virgin who may not marry a High Priest. This is considered a positive commandment for the Torah says that the High Priest must marry a virgin—the rule is phrased in the positive and not the negative. It is different from other positive commandments in that it applies only to a High Priest and not to other Jews, even other priests. Only in this case would the offspring not be a mamzer according to a very expansive reading of R. Akiva.
Note that according to this R. Akiva reads the verse, “If a man has two wives, one beloved and one hated” as referring only to the Kohen Hagadol who has two wives, one he married as a virgin and one as a non-virgin. Yes, this is weird. But you’ve been reading Talmud for a while now—lots of stuff gets weird. As I’ve said, as long as it’s possible, an interpretation can be offered, even if it seems remarkably unlikely.