>>96085589
What do you mean legally ?

You can do whatever you want "IP" literally does not exists until you actually sell the things to other people. STL are basically drawings, It's basically Fan Art.

Then you can print them. In any case, just tell anyone that you did it yourself.
There isn't any way shape or form having someone draw something for you is illegal.

Also, most of them are so starved by GW now that you can probably design a whole chapter for less than 2 starter box.