then does it imply that racism is surely going to appear?
No. Racism as we understand it today is a result of specific history (transatlantic slave trade, racial pseudo-science, mass media, etc) which established and propagated stereotypes. Racism isn't just xenophobia. It isn't inevitable just because you have races, because racism as a prejudice requires negative interactions between peoples to create negative beliefs, which isn't always going to happen. People are not guaranteed to think in racial terms either.
The Greeks and Egyptians for instance considered themselves superior to their rivals, indeed the Greeks regarded the people to their north as barbarian degenerates. But this didn't take the form of the racism we know.
The Romans offered citizenship through military service to the men of conquered peoples. The empire was a melting pot unified not by racial identity, but by Roman culture. Septimius Severus was a Roman Emperor who married a Syrian woman, and was born in Libya to a Carthaginian/Libyan father and Roman mother.
There also appeared to be something more of an enthusiastic exchange between peoples back then. The Persian empire's military couldn't be supported only by ethnic Persians, so they used their wealth to hire a lot of mercenaries. Persian nobles were especially fond of Greek bodyguards, even during Persian invasion of Greece.
In your context, there may very well be a great deal of different cultures and "races", but if the movement of people between cultures is slight then there simply aren't enough people being exposed to the other side to establish stereotypes. Foreigners are at first a curiosity, and if there is an equivalent level of technology and military power between these cultures there's no reason for one side to think as they did at the height of European imperial power; that this must be because their subjects were inferior creatures.
The history of European colonialism offers an insight into the fact people weren't always racist. Initially European traders in India often fell in love with Indian cultures. There are stories of young English traders, having made their fortune, marrying a few Indian women and settling down to immerse themselves in local culture. Unfortunately it wasn't long until this changed for the worse, and the establishment enforced rules to ensure that the British and Indians both knew their place. But that wasn't organic, cultural cross pollination is arguably the natural way people interact upon discovering exotic peoples.
It's also worth noting that prejudice between "whites" and "blacks" is a limited way of understanding prejudice against other groups. Feudalism justified serfdom by saying the aristocracy were superior. Peasants were not regarded as equal by any means. Even by the time George Orwell was writing prior to the second world, was he was putting considerable effort into confronting class stereotypes in Britain: that the elite and middle believed the working class were actually a lesser sort of people. So perhaps you should consider the issue of racism more broadly as issues of prejudice along different criteria.
If people are predisposed to view those outside of their Dunbar number unsympathetically, then that means they are going to disapprove of everyone outside of a small tribal group. And that prejudice doesn't explain racism because it's not specifically about races.
I would go as far as saying that colonial racism in the Americas was a reflection of, and required, the feudal social system of the old world, based on prejudice between people of the same "race". In the new world the Spanish replaced the upper, middle, and lower feudal classes with Iberians, Amerindians, and Africans respectively. Without the old world's feudal conceptual framework, and the experience of colonial conquest and slave trading in the new, why would people think in racial terms?