NI membership at the modest annual fee ($127 as I recall ?) includes criminal defense coverage, but no other coverage.
MOPS license insurance is real insurance with costs similar to other types of insurance (house, auto, etc). The cost will depend on what types of coverages and the amounts of coverage that you choose. Coverages can include civil lawsuit defense, USCG license defense, lost income replacement, civil suit judgment coverage, etc. I don’t think MOPS offers criminal defense coverage.