There's also a difference between state and federal charges - even if they've been pardoned, they can still be charged for related crimes.
As you said, though it's not clear, it need to be a different (though potentially related) crime.
https://www.wklaw.com/double-jeopardy-federal/
Of course, there's still the limitation that the State would need to find it's own law that the accused violated - they have no jurisdiction over Federal law (and vice-versa).
Still... it doesn't sit quite right with me. If someone is acquitted by a jury in, let's say, Rhode Island for murder. It doesn't seem right that the Federal government could step in and hold an entirely new trial thereafter. Seems to fly in the face of what Double-Jeopardy is supposed to prevent.
...and that can happen regardless of criminal conviction.
I think a more interesting question is whether there's a specificity requirement. AFAIU, that hasn't been answered, either.
This is literally all it says...
> he shall have Power to grant Reprieves and Pardons for Offences against the United States, except in Cases of Impeachment.
What gives you the impression pardons are limited to those that are "delivered" and/or "accepted". How would that even be legally demonstrated to a court.
The Supreme Court apparently ruled that way in a case a long time ago and that precedence has never been challenged (or come up again for that matter)
See https://www.youtube.com/watch?v=c9IRZ9FzWEA
But realistically if they tried to revoke a pardon today it would certainly go to the Supreme Court again and they would almost certainly rule the other way.
Looking up Grants revocation of Johnson's pardons - it's hard to find details, but it does seem like a Federal judge took issue that they were not delivered prior to the new president revoking them.
Given that there's no such limitation in the Constitution, I wonder if it would hold up to SCOTUS. ...and maybe that's why they announce them publicly these days.