I don't have private key to my btc address but i have access to my old eth address, so i signed massage from my eth address.

{
  "address": "0xd0905c09869a77830ad1a83fb8456a1de080da86",
  "msg": "raiblock signing massage for changing my eth address to 0x164a2F23c8bDb7DA85892929a255893e67F260ce today is July 26th 2021",
  "sig": "0xcd75447aea45b457b92c5bb9b01d94bf5e1bed1b5a7d41d86cec15b67ecfe68847bc7a9cac3ca 54f577d0f7e930cfa59176c8fca644c63ea669cc8284556504f1b",
  "version": "3",
  "signer": "MEW"
}


address first post in here: https://bitcointalk.org/index.php?topic=1819566.msg18777441#msg18777441