Like that?
dnf install -y epel-release
dnf install
http://rpms.remirepo.net/enterprise/remi-release-8.rpm
dnf install php53-php.x86_64
dnf install php53-build.x86_64
dnf install php53-php-gd.x86_64
dnf install php53-php-fpm.x86_64
dnf install php53-php-bcmath.x86_64
dnf install php53-php-gmp.x86_64
dnf install php53-php-geos.x86_64
dnf install php53-php-xmlrpc.x86_64
dnf install php53-php-soap.x86_64
dnf install php53-php-pecl-imagick.x86_64
dnf install php53-php-pecl-imagick-devel.x86_64
dnf install php53-php-pecl-geoip.x86_64
dnf install php53-php-brotli.x86_64
dnf install php53-php-imap.x86_64
dnf install php53-php-interbase.x86_64
dnf install php53-php-intl.x86_64
dnf install php53-php-ioncube-loader.x86_64
dnf install php53-php-ldap.x86_64
dnf install php53-php-libvirt.x86_64
dnf install php53-php-libvirt-doc.noarch
dnf install php53-php-lz4.x86_64
dnf install php53-php-magickwand.x86_64
dnf install php53-php-maxminddb.x86_64
dnf install php53-php-mbstring.x86_64
dnf install php53-php-mcrypt.x86_64
dnf install php53-php-mysqlnd.x86_64
dnf install php53-php-odbc.x86_64
dnf install php53-php-opcache.x86_64
dnf install php53-php-pecl-redis4.x86_64
dnf install php53-php-pecl-ip2location.x86_64
dnf install php53-php-pecl-yaml.x86_64
dnf install php53-php-pecl-rar.x86_64
dnf install php53-php-pecl-radius.x86_64
dnf install php53-php-pecl-crypto.x86_64
dnf install php53-scldevel.x86_64
dnf install php53-syspaths.x86_64
dnf install php53-scldevel.x86_64
dnf install php53-php-zstd-devel.x86_64
dnf install php53-php-zephir-parser-devel.x86_64
dnf install php53-php-pecl-dom-varimport-devel.x86_64
/usr/local/psa/bin/php_handler --add -displayname 5.3 -path /usr/bin/php53-cgi -phpini /etc/opt/remi/php53/php.ini -clipath /usr/bin/php53 -type fastcgi
plesk bin php_handler --reread