Tieflings have a much larger variation than Dragonborn in appearance is the thing, because they come from a wide variety of demons and devils, a lot of this variation is mentioned in the sword coast adventurers guide.

But I can give a pretty good visual example of a tiefling that doesnt follow what you expect.

https://static.wikia.nocookie.net/torment/images/e/e8/Annah.png/revision/latest?cb=20150806230824

Annah from Planescape Torment.

And then there is... the other tieflings, which... I think Annah is the only one with a tail?

https://torment.fandom.com/wiki/Tiefling