It is not possible to integrate ERC20 tokens to this plugin. I have looked at this before since it is often requested. The accounting model of Ethereum does not easily lend itself to the architecture of the plugin, so you will only be able to use Ethereum via the CoinPayments adapter. Other than that, no ERC20, sorry!
The plugin works best with UTXO tokens such as clones of Bitcoin, and there might also be an IOTA adapter soon(-ish).