I would simply not wear the brands that cause rubs.
But, if you are going to wear a layer under your breeches in summer, perhaps Underarmour Heatgear would be an option.
Anstaadt Das caused that for me…because the freakin’ deerskin was too sticky and it stuck to the saddle and I moved inside. Someone once said they must be too big then, but I don’t like wearing sausage casings. Too hard to squirm in and out of.