I have a question: does game rating somehow affect this?
I hear some people complain about the game sometime being censor during translate because the publisher want to lower the game rating. Is that truth or just a myth?
It is far far far more common in TV and film but yeah it happens in games too. Generally it comes in two forms
Actual country law type things. This can be actual laws, effective laws and sales company laws.
Germany bans (actual law, very well enforced and at a very high level) a lot of Nazi related imagery, even if you are killing Nazis. Games will be censored for this. Going by the other thread there is also some further stuff, I do quite often post uncut and cut releases for German games and there have been occasions where a company did a Europe wide release and censored the whole region's release because of such laws.
Australia, as discussed elsewhere, has serious issues with drugs being portrayed. Technically it is supposed to have changed now but before there was no equivalent to an 18 rated film for games, this meant games could not get more than whatever the lower rating was and some games had to be changed to manage this.
The UK has an interesting one from time to time. Games can be refused classification and by extension that means they can not be legally sold in the country. Manhunt 2 is probably the more notable game to have this happen for.
In the US certain companies, including very big vendors like Walmart and gamefly, will not stock either Adults Only (AO) games or in some cases even other higher end ratings. Word is Sony, Nintendo and MS will not allow them on their systems either. For a good example of things getting interesting there see Hot Coffee and San Andreas -- a rather tame sex minigame caused the game to be rerated AO.
The second form seems to be company stuff. It does not happen so much today (other than the AO stuff) but back in the 8 and 16 bit era Nintendo (
one video I just watched the first half of) had interesting policies on the matter. It went as far as things like references to religion even (Final Fantasy and the Holy spell being a good example).
Lower ratings are supposed to reach out to a wider audience, can change how you can advertise your game, what sponsors you might have in your game (in game advertising is a thing remember) and more, to this end it could be worth considering if you want more sales for your game.
Removing censorship is a fairly popular activity for ROM hackers, others also like to see what happens when games get a new release. With so much of the SNES library hitting the GBA and DS it produced some interesting examples.