If you're looking for a Welsh name with a similar meaning or sound, you might consider:
* Ewan: This is the most common Welsh spelling of the name, often used for both boys and girls.
* Iwan: This name is similar to Euan and means "John" in Welsh.
* Owain: This name is Welsh for "noble" or "good" and has a similar sound to Euan.
Ultimately, the best way to translate "Euan" into Welsh would be to choose a name that has a similar meaning or sound that resonates with you.