Greetings, cindy.w.weaver.

Thanks for joining the Community. I'm here to share about supported languages in QuickBooks Online (QBO) Global.

Traditional Chinese is the language that's currently supported by QBO Global. As a workaround, you can change your browser's language to get a Simplified version of Chinese language in QBO. 

To do this, please follow these steps (applicable to the Chrome and Safari browsers):

1. Open your Chrome browser and click on the Menu ( ≡ ) icon. 
2. Choose Settings.
3. Scroll down and click on Advanced.
4. In the Languages section, click on the Language drop down.
5. Click on the Add languages button.
6. Click to select Chinese (Simplified) and click on Add.
7. Click on the Chinese (Simplified) menu icon and choose Display Google Chrome in this language.
8. Then, click on Relaunch to restart the browser.

For Safari:

1. Open System Preferences on your Mac from the bottom menu bar.
2. Under the Personal heading click on the Language & Text icon. You should now see a list of languages in order of preference from top to bottom.
3. To change the order of preferred languages, click on Chinese (Simplified) and drag it up or down (top being 1st preference, second being 2nd preference, and so on).
4. Once you have finished setting your language preference, close the System Preferences window.
5. Now, click the Apple logo and log out of your Mac.
6. You can now log back in to your Mac with your new language preference and open a browser to see the changes.

That should do it. Your browser will now display the Chinese (Simplified) language.

Let me know if you have any other concern. I'm always here to help. Take care.