Hello,
This widget is the default WooCommerce widget and our theme does not have any additional options for this. We can help you only in case it displays wrong number of products when our theme is enabled but correct number with the default WooCommerce theme – Storefront.
If filter works the same way with both themes (Legenda and Storefront) then you need to contact WooCommerce plugin support to get any suggestions for this, we can do nothing.
Regards