npm i inertia-vue-placeholder-middleware -S

import { createInertiaApp } from "@inertiajs/inertia-vue3";
import { Inertia } from  "@inertiajs/inertia";
import  inertiaPlaceholder  from  "inertia-vue-placeholder-middleware/dist";

createInertiaApp({
	title: (title) =>  `${title} - ${appName}`,
	resolve: (name) => {
		return  require(`./Pages/${name}.vue`);
	},
	setup({ el, app, props, plugin }) {
		const  vueApp = createApp({ render: () =>  h(app, props) })
			.use(plugin)
			.mixin({ methods: { route } })
			.mount(el);
		inertiaPlaceholder().init(vueApp, Inertia, (name) => {
			return  require(`./Placeholder/${name}Placeholder.vue`).default;
		});
		return  vueApp;
	},
});

<Link href="/" placeholder="Dashboard" timeout="100"/>