Can i export mycellium wallet to bitcoin core wallet?
I know i can just transfer the coins but the tx will cost me 10$ if i do this, help is welcome.
No, you can't simply export your wallet to bitcoin core.... but if you want to move all your coins to Bitcoin Core, and minimise fees then you can import your seed to Electrum (using the BIP39 seed option during seed input)... then send all your coins to your Bitcoin Core wallet using a "manual" fee... set it to at least 10 sats/byte (or 0.0001 BTC/kB as Electrum uses)... and then use the ViaBTC TX accelerator to push it through.
This should enable you to move all your coins without incurring a large fee, but it does have a risk if the accelerator fails to work that all your coins could get "stuck" while you wait for the transaction to confirm.