Matching runs in two steps, and the order of the two steps matters.
Step one is a direct lookup. If the line carries something that looks like a SKU, a barcode or a variant identifier, the app looks it up in your synced Shopify catalogue. An exact hit ends the work for that line. This is the fast path and it covers most lines from customers who quote your codes back to you.
Step two is semantic matching, and it is where wholesale orders actually get won or lost. When the line says nothing more than a description, the app compares it against your catalogue using the full text of your product titles, variant options, tags and descriptions, then weighs the candidates against everything else it knows about the order: the pack size on the line, the unit, the other products in the same order, and what this customer has ordered before. A line reading "Lg Blue Widget" resolves to WDG-BLU-LG. A line reading "IPA 6-Pack Case of 24" resolves to the case variant rather than the single.
Customer specific part numbers get their own treatment. The first time you correct a buyer code to the right variant, that pairing is remembered against that sender, so the second order from the same customer resolves it without help. Over a few weeks the accounts you deal with most become the accounts that need the least review.
Pricing is deliberately kept out of the matching. Once the variant is known, the price comes from your Shopify catalogue and, when the resolved company sits on a B2B price list, from that price list. The buyer's document never sets your price. That single rule removes the most expensive category of order entry mistake.