I haven't had a TKR but a far far more minor incident a couple of months ago - I completely removed my right foot big toe nail dragging a heavy chair towards me. So while it healed, I stopped using my cleated pedals and shoes ( road bike ) and started using flat pedals with flat soled shoes.
Have you considered using flat pedals and flat sole shoes, just for a little while ?
Maybe you will find less stress ( possible "twist" for one thing ) on your left knee. Also you might find during the ride, you can try sliding your foot back incrementally and see how you feel.
I'm not sure the greater freedom of movement will suit your TKR situation, but you could try it if you think it's safe.
These are the ones I bought - they are very good quality.
https://www.cyclingtips.com/2021/09/...pedals-review/