In هَذَا, hāʾ is a particle of attention, without a syntactic case position.
In رَأَيْتُهَا, hā is an attached object pronoun in the accusative position.
Similar sounds do not imply identical syntax.
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Attention hāʾ vs object pronoun
Demonstratives — forms, syntax and usage
In هَذَا, hāʾ is a particle of attention, without a syntactic case position.
In رَأَيْتُهَا, hā is an attached object pronoun in the accusative position.
Similar sounds do not imply identical syntax.