As the title mentions, I'm looking for suggestions regarding underwear (mostly panties, I'm good with tops

)!
I always tuck when going out to work or activities, it does, however, get uncomfortable sometimes, notably if I sit for too long as it seems to tighten my panties on my tuck and results in irritation...

Or sometimes, my scrotum will ''spill over'' my underwear and get chafed by the seams of my panties. This one situation is very painful and prompts me to fix my tuck!
Irritation is mostly around the base of my junk, around the lower bikini part and is also worse when I'm shaved down there...

I've started letting my junk hang out untucked at home to let my irritations heal since.
I currently have hipster cotton panties, one set a size smaller and the other my size. They do have seams... should I opt for seamless ones? Or maybe another kind of material? What do you girls use?
As for gaffes, I don't know... most I've seen seem to be of sexual nature... I'm not interested in having a fake v-g-g nor showing a cameltoe... I just want to make it flat! I do own a gaffe but it creates a unsightly cameltoe bulge...

By the way, I'm pre-HRT, if it is of any help!