Specifying network: send money endpoint

Continuing my question here.

It would be great if I could specify the network when sending funds with Transactions Send Money ? For example, if I want to send MATIC, I should be able to specify the network (Ethereum or Polygon) or at least know which network the transaction will occur on. I know the Coinbase App allows this functionality as shown here , but the API does not seem to have an argument parameter for this.

This would be incredibly useful! Thanks.