What separates the options
Live-chat plugins put a chat box on the storefront and route it to your staff. The quality of the experience is the quality of your staffing.
Universal widgets come from general chat vendors and read your published pages. They answer what is written on the page and rarely more.
Native plugins receive your catalogue as data. That is what makes variant, price and availability questions answerable, and it is the only route to a live order-status answer.
On the Shopware Store the listing text rarely distinguishes these, so the practical test is whether the plugin asks to connect to your data at all.