If you want to move to a new host with your flarum, to me i would've just copied my composer.json and config.php only from my files and MySQL database. ✅
I would then upload the My database and download new flarum files, composer using create-project flarum/flarum and detele the new composer.json , and move the old one + config file.
Then punch in composer update --prefer-dist --no-plugins --no-dev -a --with-all-dependencies to get all the extensions i was using to be installed.
🤠Lol am using a mobile phone