By default, the WooCommerce LightSpeed POS will use the item id from LightSpeed as the product sku on your WooCommerce shop. You may wish to use the custom SKU on LightSpeed instead. The good news is that when a product is imported from LightSpeed to WooCommerce the initial data associated with that product is stored in the product meta with a key of _wclsi_ls_obj so you can access this meta to get the value from the custom SKU field that is on the lightspeed account. Then, LightSpeed POS integration provides a filter that can be used to set that when updating the product from LightSpeed. See this snippet below for an example of how this might be achieved:
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