Hi @jedimax
I understand that you want to prevent customers from ordering a single product.
Does that mean you want customers to order at least two products in an order?
We have a Min/Max Quantities plugin that allows you to control minimum and maximum thresholds to restrict the quantities of items which can be purchased. You can go through all its features here: https://woocommerce.com/document/minmax-quantities/
On the contrary, if you want to restrict customers from buying no more than one unit of a particular product then you can control that through the “Enable this to only allow one of this item to be bought in a single order” setting in the product details: https://snipboard.io/ENloyq.jpg
If you want to keep your product visible but not purchasable to your customers for certain time, you can try a plugin called WPC Product Timer for WooCommerce. It allows you to set a product as Unpurchasable (the product is visible but the Add to cart button is disabled).
I hope you find this info helpful!