This KB contains the workaround for fixing the above error while expanding the cluster helps them in unblocking.
Log file location - /var/log/vmware/vcf/domainmanager/
Error snippet
2023-03-1##T20:39:23.###+0000 ERROR [vcf_dm,af02dd018ab871af,e853] [c.v.v.h.s.v.HostSpecValidator,dm-exec-19] Failed to fetch IP address pool details from NSX-T cluster <nsxt-cluster-vip-fqdn>
java.lang.IllegalStateException: Unable to find any hostswitch of type VDS in the Transport node with Id: <transport-node-id>
If there is no overlay transport zone associated with the host switch, add one transport zone
2.1 Create a transport zone with name overlay-tz-<nsxt-vip-fqdn> and select Traffic type overlay.
2.2 Click on the manage option and add a tag with the name "vcf" and scope "vcf-orchestration" to the transport zone created above.
2.3 Update a standard switch in the cluster Transport Node Profile by adding this overlay transport zone.
3. Verify that the transport zone identified in the step 2 contains the VCF tags.