OVA related with famous samurai general and historical event, Tono to Issho OVA’s story begin around Sengoku period. This story is about biography of warrior at that period in different province but in comedy and parody way… I guess there also some additional character where not in the real history. Unsure its fact or not when they have doraemon and gundam that time.
original first gundam made, with cockpit view
source: NAL, wiki, AT