Modify request before calling other worker on specific URL

import { Router } from 'itty-router';
const router = Router();

router.get('/edge/backporter', async (request) => {
  request.query = '?foobar' // modify request
  // Set URL to specific URL in other worker
  request.url = '/edge/v1' // Error, cannot set read-only property
  return env.BINDING.fetch(request);
}

import { Router } from 'itty-router';
const router = Router();

router.get('/edge/v1', async (request) => { ... }