I mean Is it possible to install Symantec Endpoint protection on both Hyper-V server and two hosts?
Yes. You can install SEP clients on both Hyper-V server and host as well. Only restriction here is that you cannot install SEPM Manager on Hyper-V Server.
Which exception should I do on SEP if I install SEP on those server ?
Regarding the exceptions please check following threads:
https://www-secure.symantec.com/connect/forums/hyper-v-host-exceptions
https://www-secure.symantec.com/connect/forums/hyper-v-excepions-firewall
Recommended Exceptions for Symantec Endpoint Protection on Hyper-V
http://www.symantec.com/docs/TECH133846