Hi, I know sending btc over expired wallet address will be lost, (you can correct me if am wrong)
well possible to get the fund back ?
Expired means a wallet which private key has lost. Yes, no private key no fund to access.
Once a tx get at-least 1 confirmation then it's expensive to recover the fund, once it has 6 confirmation then forget about it. In general, no funds can not be back unless you have access the fund on the wallet it is in.