if I want to send coin to new user, he must sync whole blocks?
The new user can generate address without sync anything, but they must sync whole blockchain in order to see the transaction on their device.
I want to send coin without waiting sync. How?
1. Create SPV wallet (e.g. fork of Electrum) for regular user.
2. Use another device/tool to create unsigned transaction and use forked Bitcoin Core to sign it.