Hopefully, Margaret Qualley didn't put her foot in her mouth at "The Dog Stars" movie premiere ... but if she did, at least no clunky shoe would be in the way.

The actress showed up to the premiere of her new flick in London on Thursday wearing a gorgeous black dress and some controversial footwear ... a pair of Chanel shoes with no soles.

Margaret's shoes are very minimalist ... just a couple of block heels and some ankle straps.

Good thing Margaret had a fresh pedicure!!!

Chanel debuted the shoes earlier this year ... and it makes sense Margaret is wearing them ... she's a longtime Chanel ambassador.

Plus, Margaret's used to going barefoot in Hollywood -- with her feet famously making waves in "Once Upon a Time... in Hollywood" when she bared her soles for the camera.

Margaret recently separated from her husband, Jack Antonoff ... so maybe she's just showing off her feet for the sake of potential suitors?

Stay on your toes, folks ... ya never know where celebrity fashion's going next!