What kinda of issues will I be running into if I swap a 4.0 from a 93 ranger to a 98 ranger that had a 4.0

 

Shouldn't have any issues, but you need to used the 1998 upper and lower intakes on the 1993 engine to match wiring and fuel system
The 1993 won't have a Cam synchro/sensor, but you can use the one off the 1998, or get a new one, they can wear out

You will need a 6 bolt flywheel(manual) or flexplate(automatic) as the 1997 and up 4.0l used 8 bolt, so your current one won't fit the 1993 crank shaft

Always change the rear main seal when an engine is out
And new oil pan gasket would be a good idea just because, lol