Thank you for your quick reply but i’ve tried this one, the problem is when “hide out of stocks products” is checked in Woocommerce inventory settings (who is mandatory to make the variation swatches switch when out of stock) so then the others in stock variations will disappear from shop page even if some sizes are still in stock because the variation who is higher in the variations list (in product settings) is out of stock and the first variation in top of the list is unfortunately the one picked up for showing in the shop page.