For 20 years, I've added
electrical cords to outbuildings so I can run overhead or temporary power for
lights and heaters and mostly use what I have on hand. (A heater for doghouse in winter, heater and
lights to chicken coop. The building is wired and a male-end cord is hanging out the exterior.) Done right, replacing a plug is safe.
I do caution not to have a 30-amp plug on a 15-amp line. Connecting a heavy cord to lower power is safe, but the opposite may not be true. I always make sure all components match in amperage and gauge. Same with breaker box; switching the breaker to a higher amp if your interior wiring is lower can generate heat and cause a fire. You definitely want the breaker to trip if your current draw is too high! If you've never done wiring, hire someone who does. IMO, the cost is worth knowing it's safe.
To keep our cord from bending too much when using a 15-amp adapter on our 30-amp power cord, I simply use a bungee to hold the cord higher and create a gentler curve,