You must get your private keys derived from the seed of trezor. You can do it from tools such us https://iancoleman.io/bip39/. Of course, I recomend you using the offline version of that tool, that can download from https://github.com/iancoleman/bip39 (you can find this link from the previus one)
RE: Bitcore BTX Guide: the 2nd snapshot for BTC HODLers - free BTX | how it works