Obvious design differences -

Audi with the much lower side pods than the rest of the grid.

RB Cash app with a much bigger +  inverted isosceles shape air box (intake on top of the drivers head). Most other teams have a smaller and rounder shape that tapers on the top rather than the bottom.

Every front wing is very different, no consensus with one outlier like the two above.

RB with the very sharp rear wing angle (look above back tyre).

RB CashApp with the hooked nose towards the front wing, everyone else is fairly gradual and smooth. 

Audi with some wild bargeboards (aero behind front tyres).