Yes, you can use either charger with either bike, and you can use either voltage input with any combination of bikes and charger. Just use the appropriate adapter to convert the charger to the desired voltage supply.
The horror, selling your toys!!! Have you considered the more appropriate response, preferred by all, building a new garage, or large shop?
I'm ashamed to acknowledge your presence if your first reaction is to sell!
I find that as long as I let mine get a good night sleep, it doesn't need to take naps during the day while riding... Are you guys keeping yours up all night partying before a big ride?