Did ancient Japan ever experience or be exposed to ancient Roman warfare tactics while on the battlefield. I know that Japan was very precise in warfare and individual soldiers are very skilled in battle, but the fighting style of Japan seems very much like England during the Colonial wars. I know Oda Nobunaga was very unconventional in battle, but did the tactics of Ancient Rome ever play a part in warfare in Ancient Japan?
This more depends on your definition than what happened.
Japan did not deploy their troops in blocks of soldiers with big shields 8 to 15 ranks and they did not concentrate their mounted warriors on the flanks. But the late Sengoku and Edo battle formations were many sub-units deep.
Raiding and burning was extremely common and surprised attacks were done whenever possible. Small, local units of irregulars were used especially if available in the locality. However, quick swarms and scatter, individually hiding in among the general population backed by propaganda and indoctrination was unlikely to be a thing.