By default, the WooCommerce integration is set to import your listings when it is first set up. There is a setting that LM Support can turn on for you to automatically import new listings if you would like that feature. Otherwise, we are only pulling orders from WC and pushing quantity updates to the marketplace.
To further clarify:
You cannot add listings to WooCommerce by clicking the + as you do with eBay or other listing support marketplaces. You will be managing your listings in WC. We push quantity to them based on the inventory sources you have enabled for them in Channel Integrations as you do for your other integrations.
Because we only push quantity, the listing price, and all other fields, must be controlled on the WC side.
Pro Tip: If these listings will only live on WC there is no real reason for them to be in LM, they will just add to your overall SKU count and general management. If you would like to get listings into LM with more usable data, we suggest using Amazon Untracked Listings to get more usable data from an Amazon listing. Ultimately this creates less work for you, which makes us all happy!