Summary:
When the /replaceitem command is used, and a spawn egg is puted in the offhand slot, the colors are not correct. This affects all eggs added to the Nether update and later.

Steps to reproduce:

1. Take any spawn egg added to Nether update or later.
   For example:

   /replaceitem entity @s slot.weapon.offhand 0 allay_spawn_egg 1

Observed results:
The spawn egg in the offhand is displayed incorrect.

Expected results:
The spawn egg will be displayed as in the main hand.