Yes, there are several studies showing no differences in various task-based studies. There is also at least 1 MRI study I am aware of that didn't find sex-atypical differences, but did find a difference between the subjects and the cisgender controls.

However, and I repeat myself, as a whole - we now at around 30-40 studies most of which fall on the side of there being neurological differences in subjects with gender dysphoria. And in a few key areas we have replication of these findings too.

When you couple this together with long term treatment studies a picture starts to emerge - one of gender dysphoria being an intersex condition which response to hormone therapy and gender confirmation surgery. And most psychologists and endocrinologists now accept that when you take this approach, it is the most successful in producing happy and healthy patients.