to be honest, its possible that you are having one of those periods when the regs don't make many/any hands when you are betting. ie they are folding because they don't have a hand that can call and not because they soul read you.
I'm not saying they aren't running huds to get stats on you but I am saying you can overthink these things.
I am running into a lot more aggressive players at 5NL 6Max than 2NL with stats like 28/26 or even 38/36 and they just bet bet bet and I have to fold weak hands. When I do get a monster they fold fast.
against these guys you may need to show them that you are capable of chk/calling when you have a big hand so if they are paying attention they will see that when you play weak you aren't necessarily weak. Or play aggressively when you don't have a hand - becareful here and pick your spots - see no matter how good tehy are at poker there is no statistical way that tehy have a good hand everytime they bet but they do it cos it doesn't matter what they have if you fold alot