Shopify, Amazon, and eBay orders flow into Zoho Inventory through connectors Zoho built and maintains directly, so setting them up is mostly a matter of authorizing the connection, not building anything. Zoho Inventory and Zoho CRM get the same treatment since they're the same vendor's products, with order and stock data visible across both without custom work.
WooCommerce doesn't get that treatment, despite being one of the most common storefronts businesses actually run alongside Zoho Inventory. The same goes for most CRMs, marketplaces, and storefronts outside the short native list, where no settings-page connection exists at all.