Hi KC Lee (KCLee) 

As you are jumping between Studio versions but you did not mention upgrading your TM's, I suspect the issue maybe in the optimisation of your TM.
Please see this article here which explains how you can upgrade your TM.

Looking forward to your confirmation

Lyds

Thanks Lydia. I upgraded all required TMs before starting the current project in Trados 2022, so that should not be the issue.

KC Lee (KCLee) 

I am re-evaluating your post description and when you said: 

KC Lee said:

I enter a new target segment, it is filled up with data from TM almost instantly.

From that I mentioned your TM optimisation by doing an upgrade etc.
But now I wish to re-evaluate your meaning behind this quote and the understanding I gather from it.

I want to confirm that a user applies Auto-propagation, it is actually independent from the TM.
Auto-propagation only reads the data directly from within the SDLXLIFF file.

So with this in mind, please can you re clarify at what point is your concern felt?
Retrieving data from TM given you mentioned filled up?
Or is it as you confirm a segment and see it auto propagate below? 

If it's the latter, then this is most likely down to project related details, such as were is the project located/save to?
Local to machine or on a network drive/share drive? ?It could also be settings such as this, click here

If you are unsure the easiest test is to temporarily disable your TM.
Then to check if confirming a segment (to no TM) in order to evoke auto propagate, go quicker?

Lyds
  

Thanks for the follow-up, Lydia. It's not from what I have translated and then confirmed, but from the existing TMs. In other words, when I open a file in the sdlppx package and then move the cursor to any target segment, it is filled with content from the existing TMs. When I do it in 2015, it is instant. However, when I do it in 2022 (with TM upgraded), it takes 2 seconds and sometimes even longer time. 

Thanks for the follow-up, Lydia. It's not from what I have translated and then confirmed, but from the existing TMs. In other words, when I open a file in the sdlppx package and then move the cursor to any target segment, it is filled with content from the existing TMs. When I do it in 2015, it is instant. However, when I do it in 2022 (with TM upgraded), it takes 2 seconds and sometimes even longer time.