Top 10 flags of convenience by "tonage" in the year of 2021 are Panama, Liberia, Marshall Islands, Hong Kong, Bahamas, Singapore, Greece, Malta, China and Cyprus.
Top 10 flags of convenience by "registered" in 2022 are Panama, Liberia, Marshall Islands, Malta, Bahamas, Cyprus, St Vincent and the Grenadines, Madeira (in Portugal), Belize, Antigua and Barbuda.
I forgot what year but Liberia at one time was number one instead of panama because they were cheaper than the others and labor laws favored the owners rather than the workers.... I'm not sure if Liberia flag of convenience is sanctioned by some countries either nowadays and if there's︀ any ramifications if there are any...
For yachts look into Cayman, Netherlands and BVI