Marco Arment published a new page detailing what Overcast does and doesn’t do with your podcast. It also includes some technical information, which is worth reading, including a new upcoming feature:
In an update coming in fall 2018, Overcast will display a currency-symbol button that opens a payment, membership, donation, Patreon, etc. URL when present in the currently playing episode’s HTML body (“show notes”).
Use the rel=”payment” attribute on a standard HTML <a> link in an episode’s HTML body […]
If you publish your own podcast, make sure to read this.