Pretty much the worst idea ever one can come up with unintentionally. A simulated conversation with *one* historical person that isn't stupid and offensive takes years and years of research. There isn't a way for one person to stick a random assortment of them from just about every sphere of social life into a videogame and have it be not terrible. Writing one person is about as difficult as making a good documentary, with much, much less to show for it.
So, to write Mao, impersonal-you need to recruit several historians, at least two of whom are Chinese (Chinese-Chinese, not Chinese-American). Without it, the most a hipster programmer educated by osmosis of Cold War propaganda can output is Hitler-lite serving double duty as a caricature of Asians. Rosa Parks? The natural place to start researching is her autobiography, plus you are strongly advised to consult an African-American studies expert or a civil rights activist (who had better be black). And trying to speak for living people who are currently doing whatever they're famous for (such as Clinton or Pope Francis) in a nonsatirical context is a bad, bad, bad idea.
(I suppose a game featuring, say, the already caricaturized versions of Philosophy 101 personalities duking it out can work. Because (1) those people are dead and can handle it, (2) humanity moved forward and can handle it, and (3) the whole setup has an additional lens of "this isn't a game about actual historical people, this is a game about a freshman understanding of philosophy".)