Is it useful to fix just one bad sensor setting off check engine light?

I have a 2002 Honda CRV with over 200,000 miles on it and the check
engine codes indicating a bad knock sensor and front O2 sensor heater. I do
not want to replace the O2 sensor due to cost and risk of stripping the
threads, but the knock sensor is a relatively cheap part which I am
considering replacing. I know the engine will run in safe mode sometimes
when the check engine light is on so I'm wondering if just replacing the knock
sensor will have any effect on the engine performance. Or will it continue to
run in safe mode as long as it is detecting the O2 sensor heater failure.

Thanks, any help is much appreciated