Acceptance of a pardon is considered an admission of guilt. He’ll still be a convicted criminal.
But it won't matter for any matter of law. His Wikipedia article will show he was convicted, then pardoned. But any legal consequences of his conviction will be gone.
This is as opposed to liberal public opinion. Which also will not matter, given the Sheriff is 85 and unlikely to seek future office.
The larger benefit is, DJT has an opportunity to kick the MSM (and Left in general) in the teeth while doing a good deed in reality and in the perception of real Americans.