Unsticking an unused engine........

Definitely drive the oil pump with a hand drill to get oil pressure before turning the engine over, even by hand. I didn’t and I spun a rod bearing.

As for fluid to fill cylinders to get it unstuck, my buddy who buys stuck farm tractors uses dot 3 brake fluid ( not synthetic brake fluid) and coke cola mixed 50/50. He does this before winching it out of the field up onto his trailer. The ride home bounces the tractor a good bit and he says 1/2 the battle is won by then. You could simulate the same effect with a few palm sanders duct taped to the block.