domain based natting in sophos xg firewall

That is no NATing at all, you will need to use the Web server protection feature to achieve that.
That feature runs on port 80 or 443 and will forward the request based on the entered FQDN to the servers at the backend.

In the firewall rule you have to select "Protect with web server protection" to get into the assistant that helps you configuring it. Some webservers will need a bit more configuration if something isn't working.

Web server protection needs an own subscription. The only other thing you could do is position a reverse proxy like nginx on one server where 443 is NATed to and that then decides, which internal server will be contacted using the different FQDNs.

ok sir will check and update 

WAF is the best option as kerbora already wrote.
But DNAT (use the wizard) is also an option.
You can send every port from one external IP to another internal server with port 443.