You have lots of possibilities. If memory serves me correctly (I'm experimenting to see if what I've read works out in real life.), If you have olive eggs (The hen is laying OE's) and the father carries the brown gene, the next generation should lay more avocado colored eggs.. If the father is Ameraucana or Ee or carries the blue egg gene, the next generation will lay more of a light or minty green.
OE X OE can go in almost any direction,
There are people much more well versed than I am on here so maybe they'll give me their thoughts on the following.
This spring I'm using my blue gened rooster with my marans and welsumer hens for OE's.
But I am curious about the following planned breeding. I have mixes who lay beautiful light to medium pink eggs. I am going to put them with my rooster who definitely carries only blue genes and I would expect pale or minty green.
But going back to the parents of my pink layers, their moms were purebreds who laid technically a brown egg with a bloom (pinkish tint.) Their father was a mix who had hatched from a blue egg (Ameraucana mother) but father was from a line of brown egg layers that had a pinkish tint. (I love pink eggs.)
Is there a chance the peeps I get from these breedings in addition to the pale or minty green will go back to laying blue eggs?
That same original mixed rooster bred to my EE hens gave me girls who lay a bluish egg. I call it steel blue. Blue with a hint of grey. These birds are all excellent layers and all started laying between 4 months 5 days and 5.5 months, the later started as we were heading into the cold dark days of the end of November so I am thrilled with their performance.