I’m probably over thinking the issue since I ran a Kubota lawn tractor for 22 years 14hp Kawasaki engine on off the shelf motor oil with no issues what so ever. But, I’d like to think an air cooled engine would benefit from a robust oil designed for the high temps
Run the thickest 5-30 you can find
Fuel dilution will play a factor into your oil run
Valvoline and QS are probably the top choices for off the shelf thick oils
Run 5K OCI
Enjoy your Ecoboost !!! Fun motors to drive