What is your Shotcut version (see Help > About Shotcut)? Is it 32-bit? 20.09.27 x64
Can you repeat the problem? If so, what are the steps? Yes
Create a small project (mlt file) with rich text and elastic scale filters. Save as intro.mlt (this is used for video intro)
Start a new project and choose to open MLT XML as clip… and open intro.mlt
Add intro.mlt to timeline and export the timeline.
The Rich text is wrong. (dynamic text is OK)
I did not reproduce the problem. Using MLT XML as a nested clip only works properly when the video mode of each matches. Do yours?
Is it necessary to include Elastic Scale to reproduce it?
It is even necessary to nest a project as clip to reproduce it? Please export intro.mlt by itself and see if the result looks OK. Rich Text has a bug on systems with Windows display scale that is not 100%. What is yours (Windows Settings > System > Display > Scale and layout)? This is improved on the next version 20.10 already in beta.