Newt and Graves as Credence's dads. Can be Baby!Credence, Kid!Credence, Teen!Credence or Adult!Credence. Credence can be their adopted child or Graves is his bio dads and Newt is his stepdad, etc. Whether it uses canon setting, AR, or AU it's up to the filler. As long as Credence is raised by two loving fathers and he's happy.

Bonus:
(+) Tina, Queenie, and Jacob as aunts and uncle figures
(+) Picquery develops fondness for him as well