Who is the Centralized authority for E-Passport?

I suppose every country that issues an E-Passport has a member of some central authority or organization which manages the visa information worldwide.

No, this is not the case.

Each country must collect this information for themselfs and often do so by reading/scanning the information contained in the machine readable zone of the main page.

Some countries, like Germany, don't even have a national database where the information of their own passports are collected and therefore cannot pass this information onto some other 'central authority'.

Some countries (like mine) cant use this e-Gate, ...

The eligibility who may use an eGate is determined by each country and is often based on the likelihood of citizens of a specific country to be interviewed by an immigration official upon entry.

I suppose every country that issues an E-Passport has a member of some central authority or organization which manages the visa information worldwide.

There is no such organization.

The reason some citizens can use e-Passport in Airport e-Gate/Automated passport control is due to this central database that's shared among the countries.

This is incorrect. Each country decides who can use its automatic passport control and under what circumstances. Countries may have bilateral or multilateral agreements about this, but I am not aware of any. The systems i am familiar with are all implemented unilaterally.

Some countries (like mine) cant use this e-Gate, even if we have an e-Passport, due to being unapproved yet by this authority.

Most countries I'm aware of extend this benefit to those who can enter without a visa. In some cases, it is only a subset of those who can enter without a visa who can use automated passport control.

Countries make these decisions based on risk assessments. If you want to understand why citizens of your country cannot use a particular country's automatic passport control, you should consider the other country's attitude toward visitors and immigrants from your country.

Other answers have done a good job of explaining how e-passports work and why a central database of identity information isn't required, but have only hinted at the need and existence of a centralised authority known as ICAO: https://www.icao.int/Pages/default.aspx

ICAO provides two important roles in managing E-passport infrastructure:

• Publishing and maintaining standards (both for the physical documents and the chip protocol) so documents can interoperate between countries: https://www.icao.int/publications/pages/publication.aspx?docnum=9303
• Distributing and revocation of signing public keys so countries can trust that documents issued by other countries are valid: https://pkddownloadsg.icao.int/

The second point in particular could explain why a valid e-passport wouldn't be trusted by another country if it's not yet on the approved signers list.

To address the question of a "central authority or organization" from a technical perspective, there is also no need for such centralised control.

The information in the passport is digitally "signed" (using cryptography) by the issuing country. This is what prevents anyone from forging the information.

Each country uses their own certificate to sign their passports. At the border, the eGates will have a list of certificates to trust stored in memory, one for each country. So there's no need for a centralised authority to sign every single passport in the world.