Language and region
File | Settings | Appearance & Behavior | System Settings | Language and Region for Windows and Linux
Aqua | Settings | Appearance & Behavior | System Settings | Language and Region for macOS
CtrlAlt0S 
Aqua is available in English but also includes bundled plugins that support Chinese, Korean, and Japanese.
If your operating system is in a supported language and your Aqua is in a different language, you will get a suggestion to align them. If you don't want to see this type of notification, you can hide it.
This functionality relies on the Chinese, Japanese, and Korean language pack plugins, which are bundled and enabled in Aqua by default. If the relevant features aren't available, make sure that you didn't disable the plugin.
Press CtrlAlt0S to open settings and then select Plugins.
Open the Installed tab, find the required language pack plugin, and select the checkbox next to the plugin name.
Press CtrlAlt0S to open settings and then select Appearance & Behavior | System Settings | Language and Region.
Select the required language from the Language list.
Click Get More Languages... to install a different language as a third-party plugin from JetBrains Marketplace.
The region preference affects how Aqua or its plugins work by adapting to regional specifications. For example, it can change the URLs used to access various services, switch to a region-specific LLM provider for AI Assistant, or route traffic through a local proxy. Such adjustments optimize Aqua performance and ensure that its functionality complies with local regulations.
On the first start after the Aqua installation, you will be prompted to choose the region where you are located. If necessary, you can change the region later in settings.
Press CtrlAlt0S to open settings and then select Appearance & Behavior | System Settings | Language and Region.
Select the required region from the Region list.
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