There is a higher incidence of functional symptoms in people with EDS. Plus there is a higher incidence of hypermobility in people with FND. (Fernandez et al 2024 and Nisticò et al 2022, both studies linked below).
These articles were highlighted and shared with me recently:
ncbi.nlm.nih.gov/pmc/articl...
ncbi.nlm.nih.gov/pmc/articl...
Although, it doesn't mean if you have one disorder, you necessarily have the other.