FeatherPad is a Qt equivalent of pluma (MATE) or gedit (Gnome) and that's a good thing to have in a desktop environment.
However, to edit very large text files or to develop applications, I use Geany on MATE and was looking for a Qt replacement. Geany is said to be an IDE, but it's IMO more a powerful and fast editor for developers than a true IDE like CodeBlocks or Eclipse. However, it is sufficient for many development tasks.
Both Notepadqq and Textosaurus fit in this category and seem to be actively developed.
I've had a look at the Textosaurus project files and it only requires the following Qt modules: core gui widgets network printsupport svg. 🙂