It's a good thing you asked, Romain.

We can only check if a type of account is supported or not. We have no visibility of the projects of our engineers. The best thing we can do is send a request, as my colleague jamespaul said above, so they know how many accounts need this connection. However, PayPal still decides if they want to provide feeds for PayPal Cashback Mastercard to QBO.

As of now, the alternate option is to upload your transactions, but you can also look for an app that can directly relay your transactions from PayPal to QBO. This way, you won't have to download, convert, and import your file. 

Let me know if you have any other concerns. Take care and enjoy your weekend!