Synergy fully supports US and UK English keyboards and layouts. Most other languages work in Synergy for the majority of the specifications.
However, languages that have special characters like áéíóí or äëïöü including umlaut will not transfer the exact key/character meaning from server to client.
Other languages that are not based on the Latin alphabet such as Arabic may not transfer the exact key/character meaning from server to client.
We are working to support all major language keyboards at the moment. Unfortunately, this feature will only appear in the next major version of Synergy.
To stay up-to-date on the newest features, stay tuned to our Synergy roadmap.