Effects based on Keywords

Is there a way to make an effect that triggers based on a Keyword? For example Frightful Presence has a (fear) Keyword. I want to make an effect for a Halfling so she gets a +5 to WILL on (fear) Keyword attacks.

I can make an effect based on TYPE for example IFT: TYPE(dragon, undead); WILL: 5. but cant find a way to make it only for a Keyword (fear).

https://i.imgur.com/L5X7wyO.png

There is nothing built into the 4E ruleset to do that; so it would have to be programmed and added.

Regards,
JPG

That's what I figured. If anybody knows of any extensions or rulesets I could look at to help me build an extension for this it would be appreciated.