WR motioning inside for a running play is a tell for every team. It's a standard play.
Many teams also use it as a trap, including the Bills, where they sneak the WR out occasionally. Davis has scored off this play-action multiple times.
It's like saying that a CB following a WR in motion is tell that it's man coverage.
Also, on-field personnel is a universal tell. Subbing out a wr1 or having an extra TE usually means run, for every team.