In the later movies, Jeannie and Tony have a son, T.J. I wonder how a spin-off would have been about he and Tabitha together.... A marriage between a Witch and a Genie

There is likely fanfic out there doing just that. I rarely enjoy "crossovers" as they are called, and don't really want to see that happen between these two shows. Their background mythology just doesn't really work together. Both shows are similar in how magic is depicted, but that has more to do with how it was interpreted at the time and the limitations on special effects.

As for the plots between the two shows and the mythology which inspired them, a marriage between each would have caused great havoc between the magical elements of the families. Sorcerers are always considered to be evil to the djinn, and djinn are always seen as servants to sorcerers, meant to be forcibly captured and controlled. At least, that's how they are depicted in the stories of the Middle East. The background stories about witches and warlocks don't include the magical beings of Arabia and Persia. (In general, most mythology and their stories stick rather strictly to their own culture, and never include that of other cultures.)

If you're just thinking of a fanfic or actual spinoff concept for the two shows, I'm sure if it had been something that the two networks had wanted it would have happened. But I have never seen crossovers of shows on different networks. Normally, they are 100% in competition with each other and never cooperate on the shows they produce and air. These days it might be a different story since it's now streaming services being in competition. However, whether those in control are network 'suits' or streaming-service 'suits' doesn't really matter. Both still think the same way.

If you want to either find fanfic on that possibility, you can look at both Fanfiction.net and Archive of Our Own. Or you could write your own stories around that concept. I haven't yet tried out Archive of Our Own to see how easy or difficult it is to format a story, but I know Fanfiction.net accepts MS Word document formats.

Fanfiction.net - https://www.fanfiction.net/tv/I-Dream-of-Jeannie/
Archive of Our Own - FAQ: https://archiveofourown.org/faq?language_id=en

There is likely fanfic out there doing just that. I rarely enjoy "crossovers" as they are called, and don't really want to see that happen between these two shows. Their background mythology just doesn't really work together. Both shows are similar in how magic is depicted, but that has more to do with how it was interpreted at the time and the limitations on special effects.

As for the plots between the two shows and the mythology which inspired them, a marriage between each would have caused great havoc between the magical elements of the families. Sorcerers are always considered to be evil to the djinn, and djinn are always seen as servants to sorcerers, meant to be forcibly captured and controlled. At least, that's how they are depicted in the stories of the Middle East. The background stories about witches and warlocks don't include the magical beings of Arabia and Persia. (In general, most mythology and their stories stick rather strictly to their own culture, and never include that of other cultures.)

If you're just thinking of a fanfic or actual spinoff concept for the two shows, I'm sure if it had been something that the two networks had wanted it would have happened. But I have never seen crossovers of shows on different networks. Normally, they are 100% in competition with each other and never cooperate on the shows they produce and air. These days it might be a different story since it's now streaming services being in competition. However, whether those in control are network 'suits' or streaming-service 'suits' doesn't really matter. Both still think the same way.

If you want to either find fanfic on that possibility, you can look at both Fanfiction.net and Archive of Our Own. Or you could write your own stories around that concept. I haven't yet tried out Archive of Our Own to see how easy or difficult it is to format a story, but I know Fanfiction.net accepts MS Word document formats.

Fanfiction.net - https://www.fanfiction.net/tv/I-Dream-of-Jeannie/
Archive of Our Own - FAQ: https://archiveofourown.org/faq?language_id=en

Thanks!! I actually read a good fan fic years ago about a crossover.... it turned out the Witches had been suppressing the Genies for centuries making the Genies fear them.... when it turned out that the Genies were way more powerful than Witches but had just been put into fear. Endora had been in on this. So it came down to Jeannie facing off against Endora, in which Jeannie kicked her butt lol Jeannie's sister showed up and actually helped Jeannie this time

Thanks!! I actually read a good fan fic years ago about a crossover.... it turned out the Witches had been suppressing the Genies for centuries making the Genies fear them.... when it turned out that the Genies were way more powerful than Witches but had just been put into fear. Endora had been in on this. So it came down to Jeannie facing off against Endora, in which Jeannie kicked her butt lol Jeannie's sister showed up and actually helped Jeannie this time

I know that story, because I knew the young woman who wrote it. Her online name was Carpet, and she was a big influence in the Jeannie community in the early 2000s. Unfortunately, she died young (cancer) and never finished that story.

So, you could always finish it, or find a friend who is good at writing to do so. I probably wouldn't attempt it (even though Carpet had tried to get me to finish it) just because I am no longer much of a fan of Bewitched. I've read far more in background and ancient stories about the djinn than anything dealing with witches. It's my forte so to speak, and what I love the most.

Someone who likes both shows would do a better job of depicting both 'sides' than a one-sided writer like me ;)