Nuxt 2 cannot use import statement outside a module

[GeorginReji]

I was trying to import the package for my nuxt 2 application but I was getting an error like cannot use import statement outside a module so even after defining it as a plugin and importing in the nuxt config plugin section.

 plugins: [
    '@/plugins/vue-excel-editor'
  ],

This is the error page. If I remove the package my application is working fine.
but when I added to

build: {
    transpile: [/^element-ui/, /^vue-excel-editor/]
  }

It is working.