Our recommended way to localise dialogue is to use Dialogue Wave assets, as we have some localisation tools built around this asset type that assist you in generating per-culture dialogue sheets for recording, as well as importing the recorded dialogue (named how the dialogue sheet specified) to generate all the localised assets for you.
That said, you can use Sound Waves but the process of setting up localised variants will be much more manual (you’d need to manually import your localised audio in the correct assets). You also lose some other features of Dialogue Waves, like the ability to provide a context for the speaker/listener to change what dialogue is played (for languages that are affected by gender/plurality/rank/etc).
FInternationalization::Get().SetCurrentCulture is the correct way to change the active culture, however please note that localised assets are not currently reloaded when changing the culture. If you want your localised assets to reload, you’ll need to reload your level (or restart the game) - we’re hoping to address this now that we have content hot-reloading, however I have no time frame for when that might happen.