<p>Hello</p>
<p class="selected">Hello Again</p>
<div><span>And Again</span></div>

{
  const ex1 = $('p').next()
  const ex2 = $('p').next('.selected')
  
  console.log(ex1)
  console.log(ex2)
}

{
  const ex1 = Array.from(document.querySelectorAll('p'), element => {
    return element.nextElementSibling
  })
  const ex2 = Array.from(document.querySelectorAll('p')).reduce((prev, next) => {
    return next.nextElementSibling.matches('.selected') ? [...prev, next.nextElementSibling] : prev
  }, [])
  
  console.log(ex1)
  console.log(ex2)
}