It's your LN address not LNURL, but yes. You add these to the valueRecipient xml tags at the channel level. Buuuut, you can do more granular splits. I made a few episodes on the raw xml stuff see "bitpunk.fm unwound" You can go through what I did, by hand editing the xml. And then you might learn that sovereignfeeds.com makes a decent way to help you craft the xml. https://www.bitpunk.fm/@bitpunkfm_unwound/episodes/valuetimesplits