As said, taverns are a good starting point. I'll confirm that RP is seen in the Coffer & Coffin by Black Brush Station now and then but I won't try and say it's bustling.
My biggest piece of advice for finding RP in the open world is to keep an eye open while doing any gameplay that brings you around the map (Main Scenario or grinding or whatnot) while being willing to separate from that gameplay easily. I've met a couple of people by poking them while the main story had me in X settlement. While there may not be many constantly RP heavy areas for open RP, there are a lot of RPers on Balmung that are walk up friendly spread throughout the map, so take advantage of that as you explore.
My biggest piece of advice for finding RP in the open world is to keep an eye open while doing any gameplay that brings you around the map (Main Scenario or grinding or whatnot) while being willing to separate from that gameplay easily. I've met a couple of people by poking them while the main story had me in X settlement. While there may not be many constantly RP heavy areas for open RP, there are a lot of RPers on Balmung that are walk up friendly spread throughout the map, so take advantage of that as you explore.
"When the power of love overcomes the love of power, the world will know peace." -Jimi Hendrix
