Can anyone recommend:
Sans serif font with schoolbook a and puts circumflex on y and w like myriad pro does.
To be used for book layout for WELSH kids book - serious font, not handwriten or jokey.
ANY help = i'd be grateful !

MyFonts has a good advanced search option, where you can add characters you need – the function is hidden from the homepage though. Try this: https://www.myfonts.com/search/tag%3Ageometric+char%3A(ŵ+ŷ)/fonts/

I added “geometric” as tag, since those fonts often include a one-story a. 

download at MyFonts

 

Hey - THANKS RALF ! That's a big help. I've also found another one in the meantime:
TeX-Gyre-Adventor which is a freebie & found here:
https://www.fontsquirrel.com/fonts/tex-gyre-adventor

All the best, Gary.