The KTM Duke 200, specifically the BS4 model, comes with a stock underbelly exhaust design. While it may be possible to mount a side exhaust on the Duke 200 like the ones found on the 250 and 390 models, it would generally require modification to the exhaust system and potentially other parts of the bike.
Modifying the exhaust system of a motorcycle should be approached with caution, as it can impact the bike's performance, emissions compliance, and warranty. Additionally, it is important to check and comply with the regulations and laws of your jurisdiction regarding motorcycle modifications.
If you are interested in installing a side exhaust on your Duke 200, it is recommended to consult with a professional motorcycle mechanic or an authorized KTM service center. They will have the expertise and knowledge to guide you through the process and ensure that the modifications are done correctly and safely.