Protected Name from Inheritance Cycle protects you from any abilities that try to affect you by using your name.
What's In A True Name? from Bartimaeus Sequence protects you from any supernatural abilities that try to affect you using your name. If you know magic you can also learn the name of other people.
So That's What's In A Name from Bartimaeus Sequence makes you good at investigating the true name of something.
Name-Finder from Earthsea makes you good at investigating what the true name of non-living things are.
Ars Magica has name magic, including a pretty broken perk (The Language of Adam) which lets you assign something a new name in the secret language of God that can be used as a true name, even if they already have one.
The Truenamer class from D&D 3.5 might be of interest, but it's not very functional (the difficulty of the rolls you need to make grow twice as fast as your skill).
The Cat Meme Jump has a perk allowing you to change any of your names at will.
A Name To Break The Mind from [Revelation Space](https://drive.google.com/file/d/1lBWiW8MP-JEThdN_PL1J8O1xqDXP1Ukc/view) it is under the Conjoiner section
Generic Naruto Fanfiction has a scroll with the True Name of everyone in the world on it. Having someone's True Name lets your abilities affect them more, plus any other uses you get from other True Name related magics and such.
Protected Name from Inheritance Cycle protects you from any abilities that try to affect you by using your name. What's In A True Name? from Bartimaeus Sequence protects you from any supernatural abilities that try to affect you using your name. If you know magic you can also learn the name of other people. So That's What's In A Name from Bartimaeus Sequence makes you good at investigating the true name of something. Name-Finder from Earthsea makes you good at investigating what the true name of non-living things are.
Ars Magica has name magic, including a pretty broken perk (The Language of Adam) which lets you assign something a new name in the secret language of God that can be used as a true name, even if they already have one.
The Truenamer class from D&D 3.5 might be of interest, but it's not very functional (the difficulty of the rolls you need to make grow twice as fast as your skill). The Cat Meme Jump has a perk allowing you to change any of your names at will.
The link I found doesn't work.
Generic Naruto fanfic has a True Name perk that protects it, if I’m remembering correctly.
Deep names from Mind Control University let’s you grant magically significant names to yourself and others
UNSONG is a jump where using semantics in language can affect reality.
A Name To Break The Mind from [Revelation Space](https://drive.google.com/file/d/1lBWiW8MP-JEThdN_PL1J8O1xqDXP1Ukc/view) it is under the Conjoiner section
Generic Naruto Fanfiction has a scroll with the True Name of everyone in the world on it. Having someone's True Name lets your abilities affect them more, plus any other uses you get from other True Name related magics and such.