I feel like we have had this discussion before, but essentially European(!) Plus is both Premium Economy and Business at the same time. Business in the eyes of *A and ground handling (lounges) and mileage earning on other airlines, as well as when connecting from long haul Business Class flights. Within the system there are Premium Economy booking classes as well as Business booking classes (in which case the flights do show up as Business in some systems). I personally log my SAS Plus flights as Business. I do wonder how some companies handle this for staff travel...

SAS Plus is kinda like Schrödinger's Business/Premium Economy Class: It is either and both at the same time.