How to get Read Aloud in PDF on Okular to work?

I cannot get the "Speak Text" function to work on Okular on Linux Mint.

I've tried the following in terminal but it still doesn't work.

sudo apt-get install speech-dispatcher

sudo apt-get install espeak

sudo apt-get install qtspeech5-speechd-plugin

speech-dispatcher -d

I’ve tried the same with

sudo apt-get install qtspeech6-speechd-plugin

I have then gone to Okular settings but you cannot change the Speech-to-Text Engine from Mock to anything else.

Any advice on how to get the Speak Text, Speak Whole Document, Speak From Current Page or Speak Current Page to work?

All I want is to be able to highlight paragraphs and Okular to just read it to me