Libel must be as assertion that is not true. Photoshopping or AIing someone isn't an assertion of something untrue. It's more the equivalent of saying "What if this is true?" which is perfectly legal
Marginal note:Mode of expression
(2) A defamatory libel may be expressed directly or by insinuation or irony
(a) in words legibly marked on any substance; or
(b) by any object signifying a defamatory libel otherwise than by words.”
It doesn't have to be an assertion, or even a written statement.In the US it varies by state but generally requires:
A false statement of fact (not opinion, hyperbole, or pure insinuation without a provably false factual core).
Publication to a third party.
Fault
Harm to reputation
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In the US it is required that it is written (or in a fixed form). If it's not written (fixed), it's slander, not libel.