If I swap the 3 L V6 from an 05 ranger into my 98 ranger with a 3 L V6 would it work

 

Welcome to the forum

1991 thru 2008 Ranger 3.0l engines are interchangeable, so yes

BUT...................you should remove the upper and lower intakes with injectors from the old engine, and put these on the new engine so the wiring and injectors match the 1998 computer wiring

You will also need to swap the Cam synchronizer and sensor from the 1998 to the 2005, or get new 1998 synchro/sensor
1998 uses a 3 wire cam sensor and 2005 will be 2 wire, totally different signal types so not just a wiring difference

While any engine is out always replace the rear main seal, not expensive, but hard to get too after transmission is on