are you allowed to sell expired facial creams?

With or without the expiry date listed?

From a practical point of view, while a product may be better before it 'expires", it is not likely to poison you if it is past its sellby date.

When I first was grocery shopping in the late 60s, day old bread was deeply discounted and supermarkets sold two day old bread to pig farmers. Today, bread has a 'best before' date that can be weeks in the future. Bread is delivered weekly if sales are slow.

And a lot of things have expiry dates that have more to do with the manufacturer's bottom line than the quality of the goods. Bottled water or soft drinks for example and most tinned fruits and vegetables.