Halfling Great Weapon Proficiency

You have learned how to swing heavy weapons by using your body as a counterweight, you gain the following benefits:

• Your Strength score increases by 1 to a maximum of 20.

Additionally while you are not mounted:

• If you move at least 5 feet immediately before making a melee weapon attack with a weapon that has the Heavy property, you ignore the Heavy property of that weapon for that attack.
• You can use a bonus action to make a DC 11 dexterity check, if the check succeeds you ignore the Heavy property of weapons until the start of your next turn.

When you move through another creature's space, you can use your oversized weapon to cut the legs out from under them:

When you hit a Large or smaller creature with a melee weapon attack immediately after moving through their space, you can force the target to make a Strength saving throw (DC = 8 + proficiency + strength modifier). On a failure, the target is knocked prone. You must be using a weapon with the Heavy property

You can use this feature a number of times equal to your strength modifier. You regain all uses when you finish a short or long rest