If you are Wildshaped and then shapechange into an elf, you end Wildshape and use the stats of your normal form. It's really that simple.
Seriously.
I have no idea why people are finding this difficult, or why they're confused about which stats to use.
When you are no longer in the form that you Wild Shaped into, your Wild Shape ends.
If you quote me and ask me questions,
and I continue to not respond,
it's probably because I have
you on my Ignore list.
Congratulations.