$ sudo apt -y purge zabbix-frontend-php php7.0 php-fpm nginx
$ sudo apt -y install apache2
$ sudo apt -y remove apache2
$ sudo apt -y install zabbix-frontend-php php7.0 php-fpm nginx

Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages were automatically installed and are no longer required:
  apache2-bin apache2-data apache2-utils libapr1 libaprutil1 libaprutil1-dbd-sqlite3 libaprutil1-ldap liblua5.2-0
Use 'sudo apt autoremove' to remove them.
The following NEW packages will be installed:
  nginx php-fpm php7.0 zabbix-frontend-php
0 upgraded, 4 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/2,339 kB of archives.
After this operation, 15.5 MB of additional disk space will be used.
Selecting previously unselected package nginx.
(Reading database ... 44931 files and directories currently installed.)
Preparing to unpack .../nginx_1.10.3-1+deb9u1_all.deb ...
Unpacking nginx (1.10.3-1+deb9u1) ...
Selecting previously unselected package php-fpm.
Preparing to unpack .../php-fpm_1%3a7.0+49_all.deb ...
Unpacking php-fpm (1:7.0+49) ...
Selecting previously unselected package php7.0.
Preparing to unpack .../php7.0_7.0.19-1_all.deb ...
Unpacking php7.0 (7.0.19-1) ...
Selecting previously unselected package zabbix-frontend-php.
Preparing to unpack .../zabbix-frontend-php_1%3a3.4.4-3+stretch_all.deb ...
Unpacking zabbix-frontend-php (1:3.4.4-3+stretch) ...
Setting up php7.0 (7.0.19-1) ...
Setting up nginx (1.10.3-1+deb9u1) ...
Setting up zabbix-frontend-php (1:3.4.4-3+stretch) ...
update-alternatives: using /usr/share/fonts/truetype/dejavu/DejaVuSans.ttf to provide /usr/share/zabbix/fonts/graphfont.ttf (zabbix-frontend-font) in auto mode
/var/lib/dpkg/info/zabbix-frontend-php.postinst: 28: /var/lib/dpkg/info/zabbix-frontend-php.postinst: /usr/sbin/a2enconf: not found
dpkg: error processing package zabbix-frontend-php (--configure):
 subprocess installed post-installation script returned error exit status 127
Setting up php-fpm (1:7.0+49) ...
Errors were encountered while processing:
 zabbix-frontend-php
E: Sub-process /usr/bin/dpkg returned an error code (1)