Would it be okay to use "would be" in if-clause?

It can ideally be "Your physician may recommend you to be evaluated if you are potentially a candidate for this vaccine./ ...if you are a potential candidate for this vaccination"etc. However, going against the conventional grammar,

"Your physician may recommend you to be evaluated if you would potentially be a candidate for this vaccine", should be acceptable, except in the examinations/ English tests for students.

It depends on what you're trying to say.

If you're trying to say that the evaluation is will determine if you're a candidate, you should include that detail.

Your physician may recommend you to be evaluated to determine if you would potentially be a candidate for this vaccine.

But if your intent is that the physician already feels that you would be a candidate, and then recommends a further evaluation, you it would be better to invert the sentence to make the order of actions clearer.

If you would potentially be a candidate for this vaccine, your physician may recommend you to be evaluated.