Assuming we interpret this question in the sense that tim suggested (in a comment), as the BBC paraphrased what Muller said yesterday:
He detailed 10 instances where Mr Trump had possibly attempted to impede the investigation, but said that charging the president with a crime was not an option for the special counsel.
"The Constitution requires a process other than the criminal justice system to formally accuse a sitting president of wrongdoing," he said, in what was seen as a reference to the ability of Congress to start an impeachment process.
He said that if his team had had confidence that Mr Trump "clearly did not commit a crime, we would have said so".
Mr Mueller said he did not believe it was "appropriate to speak further" about the investigation and that he would not provide any information that was not in his team's report.
So you will probably not find any more "wink and nod" statement than this from Mueller, i.e. he isn't going to tell Congress how to do its business.
Also since impeachment is a political process, there are good reasons not to go through with it, even if one thinks the president acted unlawfully. As CNN commented:
After Mueller's statement, Pelosi again decided to strike a center chord. She didn't call for impeachment proceedings to begin, but indicated such action may be necessary in the future depending on what House committees investigating potential obstruction of justice issues find.
Polling shows that's likely the right move for now.
[Based on polling] Voters seem most open to a path in which obstruction of justice is investigated, but not via an impeachment inquiry. [...]
Launching an impeachment inquiry not supported by the public is probably seen by her [Pelosi] as a risky maneuver that puts at risk the Democratic majority. At the same time, not investigating the President would anger the Democratic base.
I should also mention that Democrats in Congress are not the only ones who read between the lines Mueller favoring/suggesting impeachment. Dershowitz also did that:
Until today, I have defended Mueller against the accusations that he is a partisan. I did not believe that he personally favored either the Democrats or the Republicans, or had a point of view on whether President Trump should be impeached. But I have now changed my mind. By putting his thumb, indeed his elbow, on the scale of justice in favor of impeachment based on obstruction of justice, Mueller has revealed his partisan bias. He also has distorted the critical role of a prosecutor in our justice system.
Virtually everybody agrees that, in the normal case, a prosecutor should never go beyond publicly disclosing that there is insufficient evidence to indict. No responsible prosecutor should ever suggest that the subject of his investigation might indeed be guilty even if there was insufficient evidence or other reasons not to indict. Supporters of Mueller will argue that this is not an ordinary case, that he is not an ordinary prosecutor and that President Trump is not an ordinary subject of an investigation. They are wrong. The rules should not be any different.
No prosecutor should ever say or do anything for the purpose of helping one party or the other. I cannot imagine a plausible reason why Mueller went beyond his report and gratuitously suggested that President Trump might be guilty, except to help Democrats in Congress and to encourage impeachment talk and action. Shame on Mueller for abusing his position of trust and for allowing himself to be used for such partisan advantage.
So Dershowitz, who is on Trump's side, [also] says Mueller did basically "wink and nod" to Congress (in order to help Democrats, according to Dershowitz).
Also, the joint official statement from grovkin's answer (that there's "no conflict" between the DOJ and the Special Counsel) should be read narrowly; just this morning (after that joint statement, I think) Barr did say that:
"I personally felt he [Mueller] could've reached a decision. He could've reached a conclusion," Barr said.
The discrepancy between the Justice Department's leaders is over its long-standing legal opinion that forbids the indictment of a sitting president.
Mueller said on Wednesday that in his view, that policy meant he could never have considered the option of bringing criminal charges against Trump.
Barr, in excerpts of his CBS interview, said he concurred with respect to charges but said he thought Mueller nonetheless could have declared whether he believed they were necessary.
In other words, Barr is saying Mueller could have said that he believed Trump should be charged — if he thought so — without the ability to actually ask a grand jury for an indictment.
"The opinion says you cannot indict a president while he is in office. But he could've reached a decision as to whether it was criminal activity. But he had his reasons for not doing it, which he explained," Barr said.
Actually Barr did comment on the Congress "wink" as well saying
"Well, I am not sure what he [Mueller] was suggesting, but, you know, the Department of Justice doesn't use our powers of investigating crimes as an adjunct to Congress."
So, for Barr there's no clear "wink" in the Mueller report, but if there was one, it would be improper.