No, a quesadilla in enchilada sauce is not different from an enchilada in any way, form factor or otherwise. A cheese enchilada is a fried tortilla filled with cheese and coated in enchilada sauce. By the time you've added enchilada sauce to a quesadilla, you've already completed the process of making an enchilada.
That's just an enchilada. They're good, but they're not quesadillas.