CountrySelect.vue

<template>
  <v-combobox v-model="country" :items="countries"  item-title="name" item-value="code" label="Land" return-object>
    <template v-slot:prepend-inner>
      <span class="mr-2">
        <country-flag :country='country.code.toLowerCase()' size='normal' v-if="country"/>
      </span>
    </template>
    <template v-slot:item="{ item }">
      <v-list-item>
        <span class="mr-2">
          <country-flag :country='item.value.code.toLowerCase()' size='normal'/>
        </span>
        <span>{{ item.title }}</span>                                                                                                                                                                                                                 ┆   1       </v-list-item>
    </template>
  </v-combobox>
</template>

<script setup>
import { ref } from "vue";
import countries from "@/components/countries.json";
const country = ref(0);
</script>