Yes, while the Mahindra XUV 3XO‘s turbo-petrol engines are punchy and exciting, they are not known to be the most fuel-efficient in real-world usage. You could definitely consider more fuel-efficient cars in a similar price range, but since your usage is largely on the highway, you want some punch too.
Check out the Skoda Kylaq, whose 1.0 turbo petrol engine has enough grunt when you need it but can also be efficient when you’re just cruising. It’s also a safe car, having scored a 5-star Bharat NCAP crash test rating. Plus, it has excellent highway composure and comfort, which should help make light work of long journeys.