Being a transhumanist, and being good at the kind of mental gymnastics that allowed him to do partial transfiguration, Harry might be able to change his Patronus into any form he likes if he tries hard enough. We know mental stuff can change Patronuses in canon: Tonks’ Patronus changed due to her feelings for Lupin, though she didn’t do it on purpose.
Being a transhumanist, and being good at the kind of mental gymnastics that allowed him to do partial transfiguration, Harry might be able to change his Patronus into any form he likes if he tries hard enough. We know mental stuff can change Patronuses in canon: Tonks’ Patronus changed due to her feelings for Lupin, though she didn’t do it on purpose.