So one “workaround” (and it truly is that) would be to put the different groups into different subsheets. Then you use the annotate function that labels parts with first free sheet after number x 100. This then groups all of your components by sheet, effectively, and I recall the last time I did that, it also grouped them by number when I imported into the schematic.
That’s a bit of a hassle, of course, and probably doesn’t make for a great looking schematic.
One thing that I normally am doing when I do layout with a lot of components is I’ll do a split screen and I’ll use the “T” key to search for parts and pull them in. Sometimes it helps to not use the actual schematic, and instead use a PDF, so that it doesn’t jump around as you are grabbing various components.
That HierPlace plugin looks interesting, Dave V makes some really great tools for KiCad.