Magento does not allow creating orders for out-of-stock products. Thus, if the product has the “Out of Stock” status in Magento, and M2E Pro attempts to create a Magento order for this product, you will see the message “Order was not created. Reason: This product is currently out of stock”. 

When the product's status changes to “In stock”, you can manually create a Magento order for the particular sale. To do so, navigate to eBay/Amazon/Walmart Integration > Sales > Orders. Tick the checkbox next to the order and submit the Create Magento Order action from the mass actions menu:

Or you can create a Magento order via the dedicated button at the top of the individual Order Details page:

Once a Magento order is created, you will see a relevant message in Order logs (eBay/Amazon/Walmart Integration > Sales > Logs & Events) or on the Order Details page: