Historian (UA)
Source: Unearthed Arcana 38 - Feats for Skills
Your study of history rewards you with the following benefits:
• Increase your Intelligence score by 1, to a maximum of 20.
• You gain proficiency in the History skill. If you are already proficient in the skill, you add double your proficiency bonus to checks you make with it.
• When you take the Help action to aid another creature’s ability check, you can make a DC 15 Intelligence (History) check. On a success, that creature’s check gains a bonus equal to your proficiency bonus, as you share pertinent advice and historical examples. To receive this bonus, the creature must be able to understand what you’re saying.