I think if you are considering going so far as a hysterectomy, you might be able to work with your doctor first to imitate the effects of a hysterectomy by using drugs to turn off your hormones for a while, to see if it makes a difference. It wouldn't surprise me if part of the package is the ovaries, but it would surprise me if that is *all* of the picture. It seems like the triggers for hormones and hormone swings also have to come from the brain. What would be the point of removing the ovaries and then still having mood swings because it's centered in your brain?
Also, ask your doctor if a series of hormone tests can be run on you before and after your period, with some done at mid-cycle as a control, to see if this is all related to hormones going up and down, and to which hormones it is related. I'd test not just estrogen, progesterone and testosterone levels but also cortisol.
Hm, that is a very interesting question. Hysterectomy is immediate full menopause. Your estrogen is severely and suddenly depleted. It would be extreme to say the least to go that route. But I do understand the mood swings. So, where I live there are psychiatrists that specialize in women's health specifically and that which relates to our cycle and hormones is a big area they work with. https://www.webmd.com/women/pms/premenstrual-dysphoric-disorder#1. Premensrual dysphoric disorder or pmdd is real. And treatable. Give that article a read and see what you think!