Convert selected Chinese text with a Mac shortcut

Set up the shortcuts

1. Open Settings → Global Shortcut. Grant Accessibility permission when prompted, then return to the app and choose Refresh to confirm the status.
2. Enable and record the keys. Turn on the global shortcut switch. Record separate key combinations for Convert Selected Text and Open Selected Text; change them if they conflict with another app.
3. Select text in the source app. Put focus in the document, select the Chinese text, then use your chosen shortcut. The Open action brings the selection into OpenCCman for review. The Convert action attempts to replace an editable selection and also shows the result in OpenCCman.

When replacement does not happen

Automatic replacement depends on Accessibility permission and the source app's selection and editing support. If the selection or destination cannot be confirmed safely, use the result in OpenCCman and paste it yourself. The original app may also reserve the same key combination, so try another recording if the shortcut never fires.

macOS Services provide another route: select text, open the source app's Services menu, then choose an OpenCCman conversion or open action if that app exposes Services. The open action is a good choice for read-only fields.