With the so called Remote Probes PRTG Network Monitor can be used to monitor several networks in different locations:
All you need one central installation of the PRTG Core Server. Each PRTG license includes unlimited Remote Probes. You can find more details in the manual.
PRTG comes in different languages: English, German, Spanish, French, Dutch, Japanese, and Chinese. You can easily switch between these languages, even after the installation. PRTG can also be translated into any other language using the PRTG Translation Tool.