It maybe a dehumidifier you'll want. - Don't run an exhaust 24/7! lower heating costs and easier to lower humidity then raise it ,,,I would go no less then this fan at the medium setting for exhausting. Set the timer for 2 min each hr.....You really want the air to around dbl exchange and as fast as you can.....
https://4hydroponics.com/max-fan-with-variable-speed-control-6-inch
Be sure your intake is HEPA quality filtered!
Looking at your plan - move the intake to the far right on the bottom - same side as shown. Exhaust and intake = opposite sides of the room. Side to side and end to end!
Keep in mind in a winter situation....That drain to the outside can freeze up and then your system is backed up.....Figure a collection system with a condensate pump and manual disposal. I have seen condensate pumps with small collection tanks, that pump directly outdoors
not freeze over 1/2" pvc drain tubes......would depend on length of winter and how cold it gets....Constant drip drains - freeze up
easy!
4' wall side fan needs to be like this -
https://4hydroponics.com/durabreeze-orbital-wall-fan-12-inch
That's what I see off hand.