Yes. Shiptheory has support for International shipping for Hermes both within the EU and Worldwide.
Hermes does does not differentiate between Hermes domestic services and international services within their service names. This means you will not see a service within your Shiptheory account named "International". Instead, you can use the existing services when shipping internationally. These are: Parcel, Parcel Next Day, Parcel Next Day Signed, Parcel Signed.
For a complete list of which Hermes services are available in which country on your account, please contact your Hermes account manager.