'Transformers' Star Jack Reynor -- Sent Us Airborne in Car Accident ... Say Pedestrians

"Transformers: Age of Extinction" star Jack Reynor allegedly went all Decepticon -- mowing down two women in a Hollywood intersection ... according to a new lawsuit filed by the women.

The women claim they were in a crosswalk 2 years ago when the Irish actor plowed into them ... throwing them into the air and onto the hood of his vehicle.

According to their lawsuit -- obtained by TMZ -- both women got messed up pretty bad ... one had injuries to her knee and back, while the other suffered head trauma and hurt her leg.

The alleged victims are suing Reynor for at least $25K.