So I have an eggling, that is going to hatch soon... Which brought up the question...Can you tell much of anything before it hatches..Like breed, coloration's...Mutations???

Only the 3 main colors (Color 1, 2, and 3)

Otherwise, everything else, you have to wait til after it hatches.
Without a genetic tester, you'll only know if it has a gene visible or not (up to 3 genes possible). When it turns into an adolescent, you'll know whether it has a mutation or not (up to 3 mutations possible).

With a genetic tester, you will know ahead of time if there are genes/mutations either visible or carried, or not there at all. c:

@Flute

Thank you! I didn't know that and now i do,Thanks!! :D

With egglings found randomly in the wild, you can only tell the coloration before it hatches and the same is true even for tagged themed egglings that you can encounter during the festivals. They will have their tag which tells you what they are but species is still listed as unknown. If you have a bred egg, you will be able to tell the species and have an idea of the traits from looking at the parents.

Hope this helps.