@pazarbasifatih This is what I did…

Installed the @growthbunker/vueflags package

quasar new boot flags - created a new boot file:

import Vue from 'vue'
import VueFlags from '@growthbunker/vueflags'

Vue.use(VueFlags, {
  iconPath: '/flags'
})

Make sure you add the boot file to quasar.conf.js boot array.

Created a new folder in /public called flags (created public if it doesn’t already exist, same level as src)

From the Vueflags web site, downloaded the flags I wanted e.g gb.svg, es.svg, fr.svg and put them in public/flags

You can then use <gb-flag code="es" size="mini" /> in your components. I wrapped it up into a Language Switcher component, e.g:

which uses this.$i18n.local to determine what flag to display in the q-btn-dropdown label slot.

Using the app alias worked, e.g.
import { Plugins } from 'app/src-capacitor/node_modules/@capacitor/core'

Thanks