sticking with one pool (not a second pool for log vols), and will worry about crossing the 32 vol later (i.e. 32 data + 32 log = 64 max)
just went for it:
made a refs small log volume (on the available storage node, but none of the others), then the larger data vol as a clusterSharedVolume if you don't already have one (but move that to the ownerNode of available storage); repeat for other cluster; do the new partnership and watch the two refs log vols automatically get converted to cluster vols!
get-clusterResource 'available storage' | ft ownerNode
icm thatNode {new-volume -storagePoolFriendlyName myPool -friendlyName whateverLogs -fileSystem ReFS -storageTierFriendlyNames performance,capacity -storageTierSizes 36GB,4GB -driveLetter L}
# you probably have a data vol, but just e.g. new data vol
new-volume -friendlyName whatever -fileSystem CSVFS_ReFS -storagePoolFriendlyName myPool -storageTierFriendlyNames performance,capacity -storageTierSizes 100GB,900GB
get-clusterSharedVolume '*whomever*' | ft ownerNode
# *if* it's not "thatNode" (like available storage), move it there
# move-clusterSharedVolume -name "Cluster Virtual Disk (whatever)" -node thatNode
# repeat for other cluster the same way (other than it's node and server name will be different; for differentiation with below new-SRpartnership cmd, let's say the other cluster's node (that it's L is, in the owner of its available storage, and csv moved to that node are) is called "theOtherNodeCluster2"
# and also note, I ran this command from thisNode (on source computer):
new-SRpartnership -sourceComputerName thisNode -sourceRGname one-whatever -sourceVolumeName c:\clusterStorage\whatever -sourceLogVolumeName L:\ -destinationComputerName theOtherNodeCluster2 -destinationRGname two-whatever -destinationVolumeName c:\clusterStorage\whatever -destinationLogVolumeName L:\ -logSizeInBytes 36GB
bam! the L: drive disappears on both cluster1 and cluster2
side note, if you remove-srPartnership, you won't see L: drives come back yet, that will automatically happen when you "remove-SRgroup -name one-whatever" on cluster1 and "remove-SRgroup -name two-whatever" on cluster2
so for sure, creating log vols as refs (not csvfs_refs like the data vols) works; i.e. they definitely get converted to csvfs_refs when you run new-SRpartnership
assuming this only works because you stick to the recommended one pool (which again, where is the microsoft documentation that spells all this out?!)
hope this helps someone