I hope Trump issues him a pardon this afternoon. This is a process crime that had nothing to do with any collusion, as was alleged by the hysterical left grasping for reasons why they lost. Mueller is firing blanks because he has nothing.
You have to be convicted to be pardoned.
I don't think there can be a pardon after pleading guilty. I don't think that Trump would pardon him anyway because Flynn lied to Pence. It seems that Trump will back up a supporter/employee for a variety of missteps, but not for lying.