Based on my experience there are certain autoimmune disorders that may flare with filler injections however, eczema has not been reported to be one of them. In the experienced hands and with proper patient selection, fillers are generally well tolerated. I recommend to have a clinical examination prior to any filler injection by your local provider.
There are some autoimmune disorders where fillers may not be indicated like scleroderma however excess and general autoimmune disorders will not affect your ability to have fillers.