From a practical perspective, I don’t see the problem here at all. They might need to build more toilets (to prevent long lines), but that’s about it.
Also picturing the “success” stories the WH already has written about this once the sub is well into it’s deployment. First emergency they meet will have them coming home to medals all around. Write ups of the awards will have all long time submariners yawning about how mundane their scare was.
There is considerable freely accessed literature on this subject about the many insurmountable (from the perspective of the the purpose of a combat submarine— readiness for combat). It is NOT about the number of heads or long lines.
Technical systems that require physical strength to maintain, fire control that cannot be performed, weapons readiness.... a slew of items, aside from the synchronized hormonal cycles and clear capability differences from males.