I'm happy to share that it was just approved earlier today! You can find it here: https://apps.shopify.com/pos-variable-priced-products-1. If this URL ends up changing, please search for "POS Variable Price Products" in the Shopify App Store.
Here is a short video demonstrating its functionality: https://youtu.be/PGQWpaCf5No?t=83
It also features the ability add tax-exempt line items, adjust inventory, and retain COGS reporting.
For any merchants who are specifically selling by weight, we also have another app specifically designed for that use case (currently with a 5-star average rating): https://apps.shopify.com/sell-products-by-weight
I'm the founder and developer - if you have any questions or feedback, please feel free to email me directly at email@example.com.