I concur with all of You: Chinese nationalist, Chinese Communists... Also Chinese peasant recruits with pikes and rifles.
I plan on create warlords army on HaT Early War WWW1 British infantry.

Non pike etc carrying Chinese people in profusion.
Refugees and displaced masses were part of the conflicts. The Chinese film ( Back to/Remember)1942 gives an idea of the scale. The peasants could face bandits, Chinese Nationalists, Japanese, Chinese Communists. They could be fed by the Japanese to undermine Nationalist authority so their major opponent was premature death through neglect and starvation(2-3 million). The Chinese Nationalist government prioritised the food needs of the army and the bureaucracy and they were often seen taking food from areas of famine. A more complex picture than two highly motivated sides kicking hell out of each other. For example the Japanese could take territory that was famine ravaged (essentially economically worthless)or undermine the governance of the enemy areas by strategic bombing or targets and they obviously chose the latter. The Japanese and Manchukuo armies were often heavily outnumbered in battles but their objectives were mainly economic hence the large coastal incursions.