Prepping Question

MegRN2008

Hi ladies!  I have received all of my newborn stash and am ready to start prepping.  Most of it is cotton prefolds and workhorses with covers, but I also got a few Newborn Blueberry Simplex AIOs.  The tag on the Simplex just says to wash once before using, but the inside absorbent material is cotton and not microfiber... so would it not need the usual 3-5 washes before it is fully prepped?  Or is it pre-prepped or something before the diaper is made?  

I also purchased some Hemp Babies Larger Weeds inserts to try for my 2 year old (I am always looking for more absorbent solutions for him).  Can I prep these with my cotton prefolds and workhorses or should I not mix the two fibers?  For some reason I feel like I have something in the back of my mind that says that oils from one will ruin the absorbency of the other?  Or maybe that was bamboo?  Or perhaps I made that up completely.  

Any insight is much appreciated... pregnancy brain is at work here  

Mandmeesh

Just wash all together. It'll work. And any diaper is okay to use after one wash, but it will definitely become slightly more absorbent after more washes and dries
ETA natural fibers become more absorbent

MegRN2008

Thanks for the input!