This is such a common thing in RPGs and it turned out so easy to do, that I know that this plugin probably already exists (maybe more than once).
Mine is special for these simple comment tags. (perhaps?)
<push> makes an event pushable
<moveIfCornered> makes event move if push up against obstacle
<withDirection> makes event face direction like driving it
<heavySpeed:number> will make the push slow down to that speed
They go in event comments and not in the note, because I wanted it to rely on pages. The events pushability is also independent of their trigger, so you can have a push by pushing and a talk by action button.
I wish I could say more about it, but all it does is makes events pushable with event comments. I allow commercial use too, as I do with all my 2 scripts. Keeping myself busy, yepper!
EDIT: I made a version 0.3, because just a slight optimization. When I rushed to correct the broken pages, I snuck the comments reader in Sprite_Character.prototype.update which turns out runs every frame, so I added some Boolean to make sure to only read the comments once per page per solo frame, and not rapidly and redundantly re-capture all the data every frame.
Update: version 0.4
I corrected a possible bug for events without pages. I'm not sure, but this might work better with events spawned with another plugin. Thanks @Edilsonsoares
Update: version 0.5 - Cognitive impairment re-fix. Thanks to @Rhino