These links may help:

https://www.reddit.com/r/operabrowser/comments/nrtf3t/import_brave_data_to_opera/

https://www.reddit.com/r/operabrowser/comments/kmx21a/importing_passwords_and_data_from_edge_chromium/ghhixig/

https://www.reddit.com/r/operabrowser/comments/ksqij4/how_do_i_import_data_from_brave_to_opera_gx/