I am 5'4" and 190lbs, so I opted for a small.
<a data-hook="product-link-linked" class="a-link-normal" href="/Forever-Lazy-Footed-Adult-Onesie-Numb-Skulls-XXS/dp/B01LWS4R04/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">Forever Lazy Footed Adult Onesie - Numb Skulls - XXS</a>&nbsp;fits good, the pockets are a bit low but big, and the crotch is not far down. Soft and comfy  and nice soft cuffs, not binding.
My big problem is that this is listed as footed, but mine is not. And no small left in the Numb Skulls......