Restructured the project structure back to the way it was, there's no reasonable way to split the modules

src/NadekoBot/_common/Services/strings/impl/BotStrings.cs

@@ -0,0 +1,101 @@
+#nullable disable
+using System.Globalization;
+
+namespace NadekoBot.Services;
+
+public class BotStrings : IBotStrings
+{
+    /// <summary>
+    ///     Used as failsafe in case response key doesn't exist in the selected or default language.
+    /// </summary>
+    private readonly CultureInfo _usCultureInfo = new("en-US");
+
+    private readonly ILocalization _localization;
+    private readonly IBotStringsProvider _stringsProvider;
+
+    public BotStrings(ILocalization loc, IBotStringsProvider stringsProvider)
+    {
+        _localization = loc;
+        _stringsProvider = stringsProvider;
+    }
+
+    private string GetString(string key, CultureInfo cultureInfo)
+        => _stringsProvider.GetText(cultureInfo.Name, key);
+
+    public string GetText(string key, ulong? guildId = null, params object[] data)
+        => GetText(key, _localization.GetCultureInfo(guildId), data);
+
+    public string GetText(string key, CultureInfo cultureInfo)
+    {
+        var text = GetString(key, cultureInfo);
+
+        if (string.IsNullOrWhiteSpace(text))
+        {
+            Log.Warning("'{Key}' key is missing from '{LanguageName}' response strings. You may ignore this message",
+                key,
+                cultureInfo.Name);
+            text = GetString(key, _usCultureInfo) ?? $"Error: dkey {key} not found!";
+            if (string.IsNullOrWhiteSpace(text))
+            {
+                return
+                    "I can't tell you if the command is executed, because there was an error printing out the response."
+                    + $" Key '{key}' is missing from resources. You may ignore this message.";
+            }
+        }
+
+        return text;
+    }
+
+    public string GetText(string key, CultureInfo cultureInfo, params object[] data)
+    {
+        try
+        {
+            return string.Format(GetText(key, cultureInfo), data);
+        }
+        catch (FormatException)
+        {
+            Log.Warning(
+                " Key '{Key}' is not properly formatted in '{LanguageName}' response strings. Please report this",
+                key,
+                cultureInfo.Name);
+            if (cultureInfo.Name != _usCultureInfo.Name)
+                return GetText(key, _usCultureInfo, data);
+            return
+                "I can't tell you if the command is executed, because there was an error printing out the response.\n"
+                + $"Key '{key}' is not properly formatted. Please report this.";
+        }
+    }
+
+    public CommandStrings GetCommandStrings(string commandName, ulong? guildId = null)
+        => GetCommandStrings(commandName, _localization.GetCultureInfo(guildId));
+
+    public CommandStrings GetCommandStrings(string commandName, CultureInfo cultureInfo)
+    {
+        var cmdStrings = _stringsProvider.GetCommandStrings(cultureInfo.Name, commandName);
+        if (cmdStrings is null)
+        {
+            if (cultureInfo.Name == _usCultureInfo.Name)
+            {
+                Log.Warning("'{CommandName}' doesn't exist in 'en-US' command strings. Please report this",
+                    commandName);
+
+                return new CommandStrings()
+                {
+                    Args = new[] { "" },
+                    Desc = "?"
+                };
+            }
+
+//                 Log.Warning(@"'{CommandName}' command strings don't exist in '{LanguageName}' culture.
+// This message is safe to ignore, however you can ask in Nadeko support server how you can contribute command translations",
+//                     commandName, cultureInfo.Name);
+
+            return GetCommandStrings(commandName, _usCultureInfo);
+        }
+
+        return cmdStrings;
+    }
+
+    public void Reload()
+        => _stringsProvider.Reload();
+}