Calorie differences

I'm not familiar with eMeals, but I have found when using the recipe tool here that sometimes MFP picks a bad entry for whatever ingredient - either it'll be the wrong product entirely (e.g. cinnamon ice cream when I entered cinnamon, as in the spice) or the serving size will be something bizarre (e.g. 4 cups of olive oil when I entered 4 tbsp). So, you gotta double check.

Edit to add: and sometimes you'll have the right ingredient, the right quantity, but the actual data entered is wrong somehow (remember, most of the database is user-generated). Example: the first entry for deli ham I picked when logging my lunch for this week was the right brand, right product, but somehow 1 oz of ham was only 8 calories, which is obviously wrong.

In addition to what @goal06082021 said*, different brands will have different cals. I've never heard of eMeals so don't know if it's just recipes or whether you get sent the ingredients but, if you're shopping yourself, using a different brand to those used in the original recipe's creation could result in a different end figure. I probably wouldn't expect a difference of 200 though.

*I've experienced all of the points mentioned, with multiple ingredients. It's very possible that even with the right ingredient and the right serving size, the database entry is wrong. You'll find this when adding entries direct to your diary too, not just when creating recipes. There's an entry for, I think, garlic or raw ginger, that apparently has about 1000 cals for a few grams. Certainly I've found some very questionable numbers when adding entries. If I see something that I think looks high but I'm not certain, and my item doesn't have any nutritional information provided, I'll select a few of the alternatives to see which is more likely to be correct.

If the eMeals app gives you a full nutrition label for your meal instead of just the calories, you could skip trying to use the recipe builder and use the "My Foods" tab instead. Create your own food using the eMeals nutrition info and log that. The downside to this is you're relying on eMeals to be accurate enough for your goals. If you can deal with the headache that the recipe builder can sometimes be, you'll be able to weigh your ingredients and get a more accurate calorie count. As others have said, you do need to check each imported line item to make sure that the ingredient and the quantity are correct. It also helps if you edit the recipe slightly before telling it to "match ingredients" - if you're making chicken, specifying "16 oz raw boneless skinless chicken breast" will probably have better results than just "16 oz chicken breast."