There are a few things you can do.
1 - Perhaps the easiest thing is to wear different pants. If you can, wear black trousers, as this will make the sweat much less noticeable. I have a wool/polyester (60/40) blend pair that dry very rapidly, and you have to actually be looking for moisture to find it.
2 - Adult diapers, while a blow to dignity and self-esteem, may help to keep you dry.
3 - If you don't need the full protection of a diaper, women's sanitation pads also work. I have used them successfully on occasions where I thought I might need the extra insurance. Even having them there can make you more confident and relaxed, which in turn will help to keep the sweating manageable.
4 - There are a number of topical creams/gels that can be applied (though perhaps you've used these already...?) You said you've tried glycopyrrolate. Have you tried it as a topical cream? If you have a prescription made up for you, a compound pharmacy can make it for you.
5 - Diet. You likely already know that HH can react to what you eat and drink, so try to avoid caffeine and other stimulants.
Lastly, we're with you, friend. We know the struggle, and it's hard. Hang in there.