Working in the same language as your local consultants and contractors reduces the risk of communication errors. Unable to change the language in Archicad? – Support site

You do not need to uninstall your current version to install a different language version. You can have ArchiCAD 27 International and ArchiCAD 27 German installed on the same machine simultaneously. They will reside in different folders within your Applications or Program Files directory.

Despite best efforts, things can go wrong. Here is how to fix the top three problems.

Your license typically allows you to run any language version up to the version number you own. However, some localizations may have regional locks depending on your specific dongle or electronic license. Graphisoft Community Switching Your Language

Your license (Full, Solo, or Education) generally allows you to run any language version, provided the version number matches your license. Changing the Library Language