hand strain in several pieces

[kjk]

There are pieces which I can play technically but not without getting strain in either hand (so technically I can't play them ).
Chopin etude op25 no1 about half way the second page I feel strain in my left hand and have to stop at the end of that page (I could continue but it is a struggle). I get the same result if I play at a very slow tempo. I make the proper movement with my left hand, loose wrist (I have normal sized hands). I don't see what I'm doing wrong. Also some strain in my left hand, but much less.

Etude opus 10 no 3, the bravura passage also gives me cramps (both hands).

The development section of Beethoven sonata opus 2 no 3, those broken triads in the right hand (12 measures), can't complete them without strain, and they don't sound good because of that.

Right hand Erlkoenig (unless one applies some adaptations). Probably not the only one here.

I don't know how to overcome this. Any suggestions

[nearenough]

On the Etude Op 25 #1 I suggest gentle lateral rotation (right to left, top note to bottom note, and back) while keeping the wrist loose. If you try to individually articulate each note that may create strain.

[keyboardclass]

Again on op 25 1, use arm weight on the on-the-beat notes BH's relaxing immediately afterwards.