Question:
In the UA on the soulknife, do you add your ability modifier to your bonus action attack with the phsycic blades?

It doesn't mention that you add your ability modifier, but it also doesn't state that this is specifically two-weapon fighting. Can you clarify? Thanks! pic.twitter.com/DfM1KaPJF0

— Kian Barbieri (@HolyTurnipGod) April 17, 2020

If a D&D rule modifies another rule, it modifies only what it says it modifies.

For example, the Soulknife's bonus action attack changes only the psychic blade's damage die. It changes nothing else about how the blade functions, so add your ability mod. to the damage. #DnD https://t.co/D7kmpl2DlR

— Jeremy Crawford (@JeremyECrawford) April 17, 2020

So this is a separate rule from Two-Weapon Fighting, correct? It doesn't merely describe how the Two-Weapon Fighting rule applies to fighting with Psychic Blades. It, in fact, has absolutely nothing to do with Two-Weapon Fighting, other than a superficial similarity, right?

— Tony Sladky (@UnitedShoes) April 17, 2020

The two-weapon fighting rule on page 195 of the Player's Handbook applies only when you take the bonus action that it provides. If you take a bonus action provided by a different rule, the rule on page 195 is irrelevant. #DnD https://t.co/8xRW5ak8pG

— Jeremy Crawford (@JeremyECrawford) April 17, 2020