Apache 2.4 /PHP7.3 /PHP-FPM /freeBSD 12 (part 2): Mysql Server57/PHP Extensions

Install Mysql server 57: 
MySQL server 5.7 installations of FreeBSD 12

Install PHP Extensions:
When you install any DB support PHP extension it will automatically install this particular DB client libraries. Chances are that these client libs will be of an old version. To avoid version mismatch simply install the database server of version you want before installing the PHP extension.
# cd /usr/ports/lang/php73-extensions && make install clean

This is a meta-port listing main PHP extension. You check the option and it will install the port of this extension. But the list is not complete, for example, pecl-* extensions you will have to install by hand:
# cd /usr/ports/devel/pecl-intl
# make install clean

Complete!