I think it's pushing it, though there's only one way to be sure, No AES-NI is going to be an issue.Specs are here.https://docs.opnsense.org/manual/hardware.html
It will be an issue with the VPN, however the CPU SHOULD be fast enough to cope with it. It's a dual core which is 'Reasonable' under the specs, Quad or above is 'Reccomended' the way I read it. However the E8200 is clocking at 2.66Ghz so it's swings and roundabouts. Try it, then post the results.