Asian-region and Japan-region are similar and different to each other in the following ways:

DIFFERENCES

• Most or all Asian-region games come with an extra instruction sheet that is in Chinese and in broken English. Japan-region games do not.

• ASIA games have different serial codes (xxxx-yyyyy) to JPN games.

• ASIA games lack barcodes at the back of the case (i.e. back insert). JPN games do have barcodes.

• Again on the back covers, ASIA games also differ in a few minor ways in text, information or images.

• This time the front covers. Most PS2 JPN-games have a small CERO logo in the corner somewhere. This is removed from the ASIA version.

• The manuals should remain most the same (Japanese) as the original with some differences in text.

SIMILARITIES

• Both ASIA and JPN games are labeled as "NTSC-J".

• JPN games are NOT localised for the Asian market. In other words, the CRC checksums of ASIA games should be the same as JPN games (Confirmation needed). Therefore, the in-game voice-acting/text and whatever else content is same as the Japanese one so don't expect any Chinese (Confirmation needed).

However, there appears to be some exceptions to the rule:

1) Sometimes they don't even bother with the cover art or changing the serial code. They just sell the JPN-version games in Asia. I believe an example is the Rockman Complete Works games for the Sony PlayStation. The only difference is that a brand new and sealed Rockman game has a red sticker saying "This software is distributed in Asia by Sony Computer Entertainment Inc. OFFICIAL PRODUCT Pricing and [For Japan Only] mark printed inside the case are not applicable MADE IN JAPAN". This sticker would obviously not exist if the game was sold in Japan. However, apart from that sticker, this is a JPN-region game for all intents and purposes, despite it being sold in Asia.

2) I don't know of any examples but I believe there are actually some games (probably PS2) that HAVE been translated into Chinese. I think it's one of the Tales of... RPG games.

Note that the above information are mostly based on my experiences with PS1 and PS2 games and for those two systems, the info should be correct for the most part.