I don't know how to import special Exim stuff or if there is even special stuff in cPanel.
If you just install Exim and exim.conf 4.5.x via custombuild, then normally you don't need any special things in Exim.
I got several customers with Outlook software, like Outlook 2013 also, which is working fine.
The only issue is that maybe on ancient Outlook software, it does not support TLS 1.2 In that case you can either make adjustments in DA or teach your customers to enable TLS 1.2 or just let them connect to port 110 and 587 without tls/ssl which is also a possibility.
Now this leaves the Office365 stuff, which is managed in the customer section of DNS itself. Set external server, change dropdown to Office365 and DNS for this is setup automatically.
So if you have special wishes, it might be better to name exactly what you need as normal outlook software is working without problems.