Yes, Uplay PC can detect if a Uplay-enabled game is already installed somewhere on your computer. 

This is how you use the feature: 

- Start Uplay PC and log in. 
- Navigate to your games library and locate the game you want to detect. 
- Click on the game tile. 
- On the game overview page, there will be a small note below the Download button: Locate installed game. 
 
- Click on Locate installed game. 
- Manually select the installation directory and confirm by clicking OK. 

You should now be able to update and launch the game through Uplay PC.

If you have any questions, feel free to get in touch!