Interac e-transfer is only available to send and receive the money within the same banking network.
Even then, if your online bank account doesn’t offer e-transfers or you receive an e-transfer from someone, and you don’t see your bank in the list of available institutions, you’re out of luck.
If you need to send money internationally or in a different currency, Interac e-transfers can’t help you, but PayPal and TransferWise can.
Even if you’re content sending e-transfers within Canada, they must fund from your bank account, but PayPal can send money via your bank account, PayPal balance, or a credit card.