Argent works on multiple blockchain networks which are built on and have the same security guarantees as Ethereum.
Sometimes when you make a transaction, such as a transfer, you will see the network you are sending from and sending to. E.g. "zkSync -> Ethereum" means you are sending from your zkSync account to an address on Ethereum, and the funds will be received on the Ethereum account.
You can also see this information in the detailed view of Activity log records (if you tap on them).
Please note that network fees across different networks can vary, and the time taken for the transfer may also be longer than expected.