Most accounts and evidence from reliable sources indicate that there is little or no influence of chin-na (or pa-kua or etc) on Ueshiba's budo.
Outside the apocryphal stories of Ueshiba studying Chinese martial arts during his foray into China (addressed in some depth in other forums here and on other boards), the best evidence for any real influence of Chinese martial systems having significant impact on Japanese budo come through the stories about Chin Gempin (see http://www.furyu.com/archives/issue8/Chin.html)
, a Chinese-born physician (or architect, depending on who you read) who shared some tricks of fighting with three ronin (Fukuno Shichiroemon, Miura Yojiemon, and Isogai Jirozaemon) and from which they then developed or amended extant versions of jujutsu that they studied and taught.
I'd venture the opinion that Gempin had some
influence on Japanese jujutsu (specifically in terms of kempo, fist methods), but that there's little evidence for direct influence of Chinese systems in any wholesale manner on the Japanese arts.
Another page about Gempin: