
Assassin's Creed Black Flag Resynced offers a wide range of language options for both the text and voice acting of the various characters you'll meet throughout the game. Since you'll probably want to play in your preferred language, here's a quick explanation of how to change the language.
Changing the language in the console versions of the game is very easy. Simply open the Menu > System > Options. Once there, choose the relevant setting depending on what you want to change:
On Steam, find the game in your library, right-click on it and open Properties > General. Look for the Language option and select the language you want to use. Bear in mind that you may need to download the language files for your chosen language. If they aren't already installed, they should download automatically after you select it.
For the Ubisoft Connect and Epic Games versions, make sure that your preferred language is selected in the relevant launcher to avoid any issues.
There appears to be an issue with the PC versions, according to reports from the game's PC community. In some cases, the language files don't download correctly even after following all the necessary steps. The problem seems to affect the Steam version in particular and appears to be a bug that should be fixed as soon as possible.