Found some to participate to the Allegorithmic during my lunch breaks, here's my entry about texturing this little guy in Substance Painter: Meet Commander MAT17 ;)
Yep! that sounds about right. Allegorithmic has a lookup table in their documentation: https://support.allegorithmic.com/documentation/display/SPDOC/Unreal+Engine+4
Hi there! I'm the Founder and CEO of Allegorithmic. We make Substance, texturing tech dedicated to game artists. Glad to actively participate as of now!