Like I said earlier, I toe-out a great deal on the right side. When I started riding as an adult, I used "touring" shoes. These were stiff under the ball of the foot and had a very narrow heel. As I put a lot of miles on them I could see a wear mark on the shoe showing me where my foot needed to be.
When I switched to clipless I had to drill my own holes in the soles to mount the cleats because of my massive toe-out. Finally, I had a machinist make me a pair of "kneesavers" before they were available on the market and I could go back to using standard mounting holes in shoes.

I have used SPD mountain bike shoes and pedals on the road bike but in my experience the SPD cleats don't have enough adjustment to get the amount of toe-out I need.
I haven't tried Speedplay pedals but I hear they have a lot of potential toe-out.

So I use extreme toe-out adjustment with Kneesavers and some shoes require shims under the ball of my right foot. At 205 pounds and climbing at least 300,000 feet per year my knees are still happy.