If you check/edit the flexview you'd see that it uses MIB queries from ctAliasInterfaceEntry=1.3.6.1.4.1.52.4.1.3.7.1.1.8.1
As far as I'd tell the B5 uses the ctAliasEntry=1.3.6.1.4.1.52.4.1.3.7.1.1.1.1 OIDs.
So you'd create one yourself to get the results for EOS.