It raised some eyebrows around the league, mainly becuase it had some similarities to the play the Patriots ran against Baltimore in the 2014 playoffs that coach John Harbaugh called "deception."
According to sources, that Baltimore formation vs. the Steelers was legal because the tight end did line up in an eligible position. The play was legal, and there wasn't even a memo sent to teams.
However, moving forward, officials will be on the lookout for such plays because teams cannot try to deceive the other team in terms of where a player is lined up. Essentially, it heightened awareness about similar plays aimed at confusing the opponent.
Williams wasn't lined up far off the line, as eligible receivers should be. That led to confusion. Officials do have the ability to call an unsportsmanlike conduct penalty if they deem the offense is intentionally trying to disguise the status of the eligible receiver. That's what happened with the Pats, whose since-banned formation featured an ineligible receiver in the slot and an eligible receiver inside.