Combining macros with modifiers

Related question: is it possible for a macro to hold down a modifier key until the next keypress? My first usage scenario would be to make a macro that places a period, space, and holds down shift until the next letter (the start of the following sentence). I use OneShot for my shift keys, so it would be even better if I could just trigger my OSM(LeftShift).

I seem to remember another thread where someone did something similar, but I can’t seem to find it.