Middle Pedal in 4th variation of k331 mvt 1?

[igot331questions]

In Mozart's k331 mov 1 variation 4 there is some left hand crossing doing lyrical melodies on the upper register. Here are a few bars where the melody is particularly chromatic on the upper left hand:



How do we approach this using standard pedaling? If we hold for the whole bar, it is muddy. If we let go on the chord changes then we lose the bass. My only solution is using the middle pedal, but firstly that will be tricky to pull off in this fiddly situation, but also did Mozart have a middle pedal?

Would love to know your thoughts, thanks!

[lelle]

the lower stave only contains 8th notes so they should not linger through the bar via pedal, middle or otherwise

I'd play them with a kind of portato.