There is some debate about whether left-handed folks should play ukulele or other instruments in the opposite hands and string them in the opposite direction. As someone who comes from the classical world and music education world, my view is that all instruments should be played in the traditional fashion unless someone has a limb difference or other disability that makes it impossible to play traditionally. Think about symphony orchestras that are filled with people – and have a very high proportion of lefties! – who all play their instruments in the same direction. There really is no reason for most left-handers to play an instrument flipped, and it can be limiting in terms of finding instruments and finding teachers who are willing to teach this way. While ukulele is a great instrument for social music-making and learning beginning music skills, it is not an instrument that one can typically use to do things like play in youth orchestras, get scholarships to colleges and so forth. If a child finds they have musical aptitude, they will probably need to play a classical instrument in order to continue their musical education, as most high-level music education in the U.S. is based on classical music. Ukulele skills transfer nicely to orchestral string instruments (violin, viola, cello, double bass), which are always played with the left hand on the fingerboard except in the event of disabilities that make this impossible. Learning to play ukulele in reverse from the standard setup means that the ukulele skills will not transfer to other instruments and the skills will have to be re-learned.
In my beginning group ukulele classes (both online and in-person), I require students to play in the standard fashion, in which the right hand strums and the left hand fingers the chords, unless previously contacted to discuss a relevant disability. In a group class, if students are playing in different orientations, I would need to give two directions each time I give a direction, and I do not wish to overwhelm and confuse students.
Also, every single student who has arrived at my classes stating they are "playing left-handed" has not actually set their ukulele up correctly for left-handed playing, which means they had the wrong strings and wrong notes positioned relative to their hands, had no possible way to play correct notes, and were playing incorrect notes that throw off the rest of the class. This is not fair to other students in the class, and it does not allow the student to learn any useful skills.