They will fit. Whether or not you will need spacers is a different story. Without knowing the backspacing/offset that will be a hard question to answer. If they are aftermarket wheels, the backspacing could be different than stock Explorer wheels. I am sure there are some wheel experts on here that can help out more than I can.
Also got to look out for the hub centric wheels as some of them have a smaller center hole than others and have to be opened up.
All aftermarket wheels will have a large enough center hole though.
I have a set of mustang wheels on my ranger and had to open up the centers for them to fit without spacers. Never tried them on the jeep though.