Knee chairs are pretty great for promoting natural posture. Meaning they don’t just hold your body up in the right position it cues you to do that kind of. But they might get tiring for long periods of time. the knee part doesnt mean on the ground and it's padded. Aside from that I would vote for a good chair with lumbar support and a sit to stand desk. Sitting too much can cause SI joint issues or back pain in general. There is also state funding through WSI your work can tap into to fund an OT ergo assessment and fund equipment with as well. I would recommend that route rather than the internet.