https://medium.com/@BryanFajardo/how-to-use-vue-js-inside-of-sweet-alert-2-modals-31da49e2e4d8

vue-sweetalert2.js

// Display a vue component with bindings and return the props data
alertVue: async ( options, componentName, propsData ) => {

    const ComponentClass = Vue.extend ( Vue.component ( componentName ) );
    const instance = new ComponentClass (
        {
            propsData: propsData
        }
    );

    const result = await Swal.fire ( _.merge (
        {
            type             : null,
            allowOutsideClick: false
        },
        options,
        {
            html        : '<div id="alertVue"></div>',
            onBeforeOpen: () => {
                instance.$mount ();
                document
                    .getElementById ( 'alertVue' )
                    .appendChild ( instance.$el )
                ;
            },
            preConfirm: () => instance.$props
        }
    ) );

    // Destroy our dynamic instance
    // Necessary? Not sure..
    instance.$destroy ();

    return result;

}