Merging several accounts into a single account, even if they are in the same region (EU, NA, etc.), is technically impossible.
Each account is linked to a specific email address and has its own unique identifier. That's why you can not merge different game accounts.
Unified Wargaming.net ID Account
To sign in World of Tanks, World of Warplanes, World of Warships, World of Tanks Blitz you can use a unified Wargaming.net ID account. This means that if you are registered in one of these games, then you can use your credentials (email address and password) to enter any of them.
However, the in-game assets in these accounts will not be the same, since these games are designed for different platforms.
The only shared things are:
- Gold and Free Experience in World of Tanks and World of Warplanes
- Premium Account in World of Tanks, World of Warplanes, and World of Warships
World of Tanks Console
Merging World of Tanks accounts for personal computer and for Xbox 360, Xbox One, Xbox One X, and PlayStation 4 consoles (World of Tanks Console) is also impossible.
World of Tanks Console is intended only for playing against other tankers using console Xbox 360, Xbox One, Xbox One X over Xbox Live, and PlayStation 4 over PlayStation Network. In this case, when playing on consoles, Xbox Live and PlayStation Network profiles are used instead of the Wargaming.net ID account.