Good day,
I've added sury.org repo, and installed PHP 7.4 & 7.3. Plesk automatically displayed PHP 7.4 by OS vendor, it works perfectly. PHP 7.3 did not automatically populate.
I added it via CLI:
/usr/local/psa/bin/php_handler --add -displayname 7.3lts -path /usr/bin/php-cgi7.3 -phpini...