It is not too much trouble, but it will cost you a bit extra on visa fees depending on your passport.
Microlight is only done in Zambia, therefore you have to catch a transfer which is very easy to arrange (you can Contact us for that and we can do it for you) it will cost $15 each way per person.
So that is no problem at all and it is quite quick to cross the border, takes about 30 minutes.
You need to purchase a day tripper visa to enter Zambia (US$20) and you will need another visa when you re enter Zimbabwe so make sure you buy the double entry visa when you first land in Victoria Falls airport.