gatsby-node.js

const path = require("path");

const pageTemplate = path.resolve("gatsby-page-template.js");
const pagesQuery = `
  query Pages($language: String!) {
    wordpress(language: $language) {
      pages {
        nodes {
          id
          slug
        }
      }
    }
  }
`;

const languages = ["nl", "en"];

exports.createPages = async ({ graphql, actions }) => {
  const { createPage } = actions;
  for (const language of languages) {
    const result = await graphql(pagesQuery, { language });
    for (const { id, slug } of result.wordpress.pages.nodes) {
      createPage({
        path: `/${language}/${slug}`,
        component: pageTemplate,
        context: {
          id,
          language
        }
      })
    }
  }
};

gatsby-page-template.js

import React from "react";
import { graphql } from "gatsby";

const Page = ({ data }) => {
  const { title, description } = data.wordpress.page;
  
  return (
    <div>
      <h1>{title}</h1>
      <p>{description}</p>
    </div>
  );
};

export const query = graphql`
  query Page($id: String!, $language: String!) {
    wordpress(language: $language) {
      page(id: $id) {
        title
        description
      }
    }
  }
`;

export default Page;