Short question; does ROS support RFC7911 - https://datatracker.ietf.org/doc/rfc7911/ ?

Thanks

But if you want to configure a load balancing scenario, OSPF works as an IGP (which supports ECMP), and you need to configure BGP as en EGP, so the OSPF is the one who cares about, quick convergence, load balancing and distribution of internal loopbacks, then you'll need some iBGP sessions between your routers, and you'll see that the prefix x.x.x.x is being advertised by the neighbor y.y.y.y; but the OSPF tells you that you have two load balanced paths between this too routers (two routes to the same loopback address), so the recursive routing will do the rest