Check it out yourself ... the 26-year-old reality star stepped out in a strapless cream-colored sheer flowing dress at the Jean Paul Gaultier show Wednesday -- a far departure from her bold, skintight outfits that she's been rocking of late.

As you can see ... Kylie paired the stripped-back ethereal sleepwear-inspired dress with towering heels, minimal makeup ... and old Hollywood-style locks. A very soft 'fit, for sure.

She was certainly feeling herself in the moment, and even posted some clips of herself from the show -- but, unfortunately, a lot of people had less-than-nice things to say about her appearance ... namely, the notion that she looked a bit "old," at least in their eyes.

One person cruelly commented she was "aging in dog years," while another added she looked 47 -- and a third said she'd ruined her face. Like we said, very jerk-y remarks.

Nonetheless, Kylie put in her best effort to keep up appearances in her BF's native France ... probably sensing her Cali style wouldn't cut it in Paris -- a city at the pinnacle of high fashion.

While TC's been by KJ's side at several public events since their romance emerged, she was ridin' solo at the show ... although, there was a familiar face in the mix ... one Jordyn Woods!

Remember, they seem to be on good terms now -- as the duo appeared to bury the hatchet last year after Jordyn's kissing scandal with Tristan Thompson from years earlier. Bottom line here ... KJ appears to have been in good company with a pal in tow.

BTW, Kylie's look here was echoed by lots of other celebs/models who were in the JPG show as well ... lots of different getups, but a similar theme -- simple, yet elegant.

Bella Thorne and Noah Cyrus were among those in attendance at JPG ... plus lots of others. And FWIW, PFW has been a huge draw this year for other stars looking to strut.