You can open Unreal Engine 4.27 and then open Quixel Bridge, but the standalone application (so not the plugin for UE 5). The standalone Quixel Bridge still has acces to the Metahumans 4 (the Metahuman category is divided in versions 4 and 5). You can then import a Metahuman 4 into a UE 4.27 project, save it, then migrate the project to UE 5 by opening the project in the UE 5 project browser.