you can use a dedicated IP for each website (with subdomain or domain mapping, not with subfolder multisite), but it’s not a common EasyEngine configuration, so you may have to edit or create some nginx configuration yourself.
To use a dedicated IP for a website, you just have to edit the file ssl.conf available in /var/www/yourdomain.tld/conf/nginx, and to set the IP in the directive
listen, it should look like :
listen 192.168.1.1:443 ssl http2;
But to add more domain, you will have to create a new nginx vhost for each domain and to set the IP