DialogueContainer.cs

[System.Serializable]
public class DialogueContainer : ScriptableObject
{
    //Unique ID used as ref
    public string ID;
    //All variants of the text to display
    public string contentText;
    //The response options
    public List<DialogueOptionContainer> responseOptions;
    //The tags this dialogue uses
    public List<string> tags;
}

DialogueDatabaseFile.cs

[CreateAssetMenu(fileName = "Dialogues", menuName = "Dialogue Database", order = 1)]
public class DialogueDatabaseFile : ScriptableObject
{
    public List<DialogueContainer> dialogues = new List<DialogueContainer>();
}

DialogueOptionContainer.cs

[System.Serializable]
public struct DialogueOptionContainer
{
    //Text to display as line
    public string optionText;
    //The reference to what DialogueContainer the dialogue goes when chosen
    public DialogueContainer optionRef;
}