Does anyone know of a stitch pattern (not crocheted) that is openwork but will not stretch. I would like to make a soap mitten that when hung in the shower won’t stretch too much but s still open enough to let suds through.

Try a garter stitch on larger needles. If you’re using a worsted, use 10½s or 11s.

Also try purse stitch, an extremely easy lace. Every row is the same.

Cast on an even number of stitches.
Knit 1, *yo, purl 2tog. Repeat from * to last stitch, knit 1.

Try help or linen yarn to reduce stretching.