Hi team. is this a acceptable practice to use multiple useFeature in a page ?

const Sample: React.FC = () => {
  const feature1 = useFeature('feature1');
  const feature2 = useFeature('feature2');

  return (
    <>
      <Button color={feature.value || 'blue'}>feature1</Button>
      <Button color={feature.value || 'blue'}>feature2</Button>
    </>
  );
};

export default Sample;

And also do we get experiment for multiple a/b testings in trackingCallback: async (experiment, result) ?

Yes in general this is fine. https://docs.growthbook.io/faq#can-i-run-multiple-ab-tests-at-a-time

Thanks, so can I expect two logs in the following code ? ( with enabled namespaces )

trackingCallback: async (experiment, result) => {
    console.log(experiment, '<<<<<');
  },

I only see one log for the two experiment:

You could expect two logs if both features are in a test. I suspect an A/B test was not set up for one of them.

you may also want to check the FAQ for when the tracking callback gets called as it isn't called in all cases: https://docs.growthbook.io/faq#why-is-the-trackingcallback-not-firing-in-the-sdk