We've gone back and forth on this in the past (different scoring rules for different positions) and at this point we have not enabled this feature. The reasoning is that this is a very uncommon scoring setup and adding the functionality would exponentially increase scoring rule input for all members. FFPC is the main instance where something like this is used, w/the 1.5PPR for TEs.

What most of our members in this situation do is simply have two sets of scoring rules, one for TEs and one for the rest, and then either combine the two, or simply go off of positional cheat sheets when drafting.

Another option is Draft Analyzer (Free with your 4for4 subscription). Draft Analyzer  does support more complex rule sets like this.

Further reading on this subject: How Does 1.5 PPR Scoring for TEs Impact Draft Strategy?