Hi! I am in a similar situation-- I am in my sixth year teaching and found myself wanting to do more outside of it. I cannot speak to applying to Ed.D. programs, but I did apply to PhD programs. I only had a tiny tiny amount of research experience when I got my master's.
In any case, I did get interviews at Penn GSE and Harvard GSE with little research experience (and an unofficial offer of admission at the former, still waiting to hear back from the latter). As long as you can explain why you want to make the switch, and how your current skills are applicable to what you want to do, I think it's totally possible to get into top programs.