Nando Delgado

Super Duper SMTP is a very simple to use plugin to send all email through SMTP and avoid delivery issues and extra set up on the WP admin panel. Just install it, activate it, and you’re good to go!
The free version of this plugin supports up to 10 emails per month per domain, with premium pricing starting at $1.49 for up to 100 emails per month.

Super Duper SMTP

nikita.global

Create your own notification bot which will send emails to your dashboard users via telegram.
Sends all mails to telegram user via your own bot. 
No need in many other plugins as you can use any email notifications which will be redirected to telegram
<a href="https://nikita.global" rel="nofollow ugc">https://nikita.global/</a>
Your website should support https.
** Message Filters ** 
Currently can send mails as plaintext, files, subjects only and truncated message. 
You can extend this range using the filters – see source code.
This plugin makes HTTP-requests to 3rd party service <a href="https://core.telegram.org/api" rel="nofollow ugc">Telegram API</a> 
to send notifications.

NG-Mail2Telegram

very good!

Create your own notification bot which will send emails to your dashboard users via telegram.

Super Duper SMTP vs NG-Mail2Telegram