Crankshaf

Use an impact or a breaker bar with a long handle with the correct socket and brace it underneath observe pulley rotation and crank the engine over-

There is no easy way around this situation and it happens to many types of motors.
Unfortunately you cannot apply much heat to the area without risking damage to the front main seal and pan seal. If you intend to replace all seals near the pulley that might get damaged, applying heat is a good wayu to get it to break free.
If you have the time, WD-40 or PB-Blaster is not an Urban Legend.
I prefer PB Blaster. Soaking the contact area as much as possible, then cleaning off the stuff it cleans off, i.E, rust other sorrosion and sometimes threadlock or bearing lock, with brake cleaner and then saoking again can work wonders.
Hope this helps.