horde:
https://www.wowhead.com/item=65362
https://www.wowhead.com/item=65364
alliance
https://www.wowhead.com/item=65361
https://www.wowhead.com/item=65363

the four aren't account pets and collecting in a character still show missing in account mode.
making what the faction opposite pets are imposible of collect.

This is true. ATT doesn't have specific non-account-wide logic for these few pets. Also technically the seahorse from Vashjir is character specific.

We do have a fake collecting logic. If you collect horde, you will get Alliance credit & vice versa.

As they are not accountwide, you will have to collect them with every character.