Start with the WooCommerce order scope
Separate Belgian domestic B2B orders from B2C sales, EU cross-border sales, marketplace orders, subscriptions, refunds and mixed carts. Belgian official guidance says structured electronic invoices apply from 1 January 2026 for transactions between Belgian VAT-liable businesses, with limited exceptions. That means the webshop must know when an order is really a Belgian B2B invoice before it sends anything through Peppol.