I received the following response from support in July:
“It’s not available in the API yet. If you use our shipping presets you would also have to add that payment method to each listing via Seller Hub after each submission or revision.
If the eBay Business Policies support this now on the eBay site, you could switch to those as we don’t send the details, just the Policy ID.”
Make sure you really look at all of the ins and outs to make sure you aren’t going to have issues before signing up. Once you’re in, your’re in and there is no out. You can’t accept paypal at this time in conjunction with managed payments. I also read there are issues with international orders. If you have a capital loan with Paypal, you will be in violation of your Paypal loan agreement. I can’t remember the other issues sellers have ran into. Definitely research it thoroughly before jumping in.