child_processから起動させる

方法1

#!/usr/bin/env node

const { spawn } = require('child_process')
const subprocess = spawn('./node_modules/electron/cli.js', ['./index.js'], { 'stdio': ['inherit', 'inherit', 'inherit'] })

方法2

PATHを通してコマンドを叩く

const { spawn } = require('child_process')

let env = process.env
env.PATH += ':./node_modules/.bin'
let subprocess = spawn('electron', ['index.js'], { env: env, detached: true })
subprocess.on('close', (code) => {
    console.log(`code = ${code}`)
})
subprocess.stderr.on('data', (data) => {
    console.error(data.toString('UTF8'))
})