Textroduction 

Introduction done through text messaging platform.

Please let this serve as a textroduction between John Doe and Jane Doe.

Textroduction by virginiacannabislawyers March 17, 2022

Extroduction 

Opposite of introduction. A way of leading out of a topic.
A short form is extro

It can also be used as a verb, in the opposite manner of the word introduce.

John read the extroduction of his favorite book.

Let me extroduce Mr. T, the man who needs no introduction.

Extroduction by Dr. Fred Manly January 20, 2009