I think I might have had a menopausal midriff my entire life! Or at least, I've always had a rounded little tummy even when very slim now I am not slim all the weight goes on there and I agree that past a certain point, it does have a barrel like ageing effect.
My tips are all generic, I don't have some magic dress that will solve anything, and I don't wear shapewear as it makes me feel sick and constricted, so it's all hanging out for me anyway.
My tips are- first work the core quite a lot, you can dance at home, get an exercise bike and lean back a lot, do specific tummy exercises, go to a gym. I look 100% better with a small amount of muscle tone and standing up straight. The fat sits on top but so what.
The second is that I go (except in mid-summer) for a few similar looks. One is black strappy cami, black trousers (say linen in summer, cotton, whatever) and then a coloured shirt on the outside (e.g. linen khaki in my case as I am quite pale). Used to do the same at conferences, always have a (nice) black skirt, cami and a cool jacket, also same for going out with leather jacket. The line of the black or navy all the way down is very flattering compared with things cut off at the waist.
Also, and this is a personal thing as I know everyone loves dresses on here, but dresses are hard work for people with tummies as nearly every style exaggerates the stomach and 'nipping things in' at the waist with belts doesn't work. I wear separates all the time- so long skirt in denim or cool summer colours, chunky sandals or trainers, cami and a loose shirt (again, linen, cotton). Or black cami, black fitted shirt, white floaty skirt, lots of gold accessories.
Finally, try adding interest elsewhere, one of my fave casual looks is dark straight jeans (quite tight), a floaty navy top with a strappy cami underneath. No tummy in sight, but still a bit nicer than say a plain cotton round neck. I love V neck everything or shirts which are quite open.
Or do what my very good friend does, wears what she wants and ignores her stomach which has always looked a bit pregnant. No-one gasps.
Just some ideas!