So repercussions tend to range from nothing, through wagging fingers, slaps on the wrist, to sanctions, UN resolutions, UN-sanctioned wars, or if you really piss someone off, non-sanctioned wars.

I don’t think Belarus will be invaded, and I guess Russia would veto any particularly nasty move in the UN, so really this leaves stern words and some unilateral sanctions against the Lukshenko regime. Doesn’t seem like overwhelming penalty (though well-targeted and enforced sanctions can bite quite badly).