I have a bike built with a child seat on the back used for carting around LMTTM Junior.

We pack light for excursions (to the park 😉 ) but occasionally use the bike for shopping runs.

A front basket/carrier type thingy would be useful but preferably one not made of wicker and requiring a flower 😆

The fork doesn’t have any eyelets so a rack option won’t work so thinking bar mounted. Mounted on Mary bars 🙄

Any suggestions?

I’d have thought you’d get a KlickFix handlebar bracket on a Mary bar which would give you plenty of options, provided that they cleared the curves of the bar – you can also get an extender for that bracket which would take the bag out past the curves.