When redistribute routes from bgp to OSPF, the community will not take effect.
Actually, while a route is redistributed into OSPF, it is not redistributed from bgp routing table directly, but from IP routing table.
The bgp routes are put into IP routing table first, then redistribute this routes from IP routing table to OSPF table. So it will loss the community attribute while put bgp routes into IP routing table.
Use ip-prefix to filter the routes while redistribute routes from bgp to OSPF. This limitation is not only for NE20E, but just a limitation of the VRP platform. So Huawei router and switch may have the same issue. The redistributed is from IP routing table, not from bgp routing table, so we can’t filter according to communities.