Hide "Outgoing email" transaction

I am looking for a simple (or not) way to hide transactions, which are created, when outgoing mail is sent.
Part of our team noticed, that it is really hard to get through all of these messages and it would be better to make them disappear.
I have found a topic describing doing so by using callbacks:
However this article was written few years ago and right now, it seems to be outdated.
Do you know any idea, how to do this in +5.0.0 RT version?
Might above article be the way to do so, just by modyfing callbacks a bit?
I thougtht, there might have been additional filter added.
Thanks in advance for your help!

There is a right to show those transactions, do you could resolve that right.

Also there is this extension:

Or Config option to show only Correspondence transactions. But this has not such fine-tunning as the proposed extension.