There is no indication that he has done so. There would be no need for him to do so. The DOJ was going to go after the cause of January 6 with or without Presidential orders. What you have not owned up to is the fact that Trump said that he believes that he has that right. If I remember correctly I do believe that Trump did attempt to go after Hillary in such a way, but his handlers stopped him from doing so.
Let me see if I can find it.
Yep, Trump tried to do it. And this article answers why Biden has not done it:
The encounter was one of the most blatant examples yet of how President Trump views the typically independent Justice Department as a tool to be wielded against his political enemies.
www.nytimes.com
"
President Trump told the White House counsel in the spring that he wanted to order the Justice Department to prosecute two of his political adversaries: his 2016 challenger, Hillary Clinton, and the former F.B.I. director James B. Comey, according to two people familiar with the conversation.
The lawyer, Donald F. McGahn II, rebuffed the president, saying that he had no authority to order a prosecution. Mr. McGahn said that while he could request an investigation, that too could prompt accusations of abuse of power. To underscore his point, Mr. McGahn had White House lawyers write a memo for Mr. Trump warning that if he asked law enforcement to investigate his rivals, he could face a range of consequences, including possible impeachment."
If Biden had done it, rather than allowing it to happen as it appears that he did, he could possibly have been facing charges as well.