I can't give an answer to OP's main question because I don't have multiple Trezor devices. I built myself a PiTrezor in the past and could simulate two or more Trezor One hardware wallets by using multiple microSD cards for the PiTrezor if I had the time and motivation to do it. (Likely won't happen any soon, sorry.)

But I'm not using my PiTrezor for more than Testnet coin wallets at best.