MyMonero is a Monero only wallet service, we only support XMR.
If you send any other cryptocurrency into your MyMonero wallet, those funds will be irreversibly lost.
Our wallet service allows you to store Monero (XMR) only.
If you would like to convert another cryptocurrency into XMR, you can use an exchange service. By using your MyMonero wallet address, the newly exchanged XMR will then appear in your wallet.