I don't use outdoor flash, mainly because the majority of my portraits are with horses, or ponies. I can't risk the off chance a pony will spook from a flash and hurt a kid. It is unlikely, but horses are large and unpredictable
I usually wait until the golden hour and shoot then. It is a short window and I do shoot them facing into the sun. It is usually low enough they are not squinting.
It is a short window of time and very weather dependent. Again, I am no master, it is just how I do it