List.FilterByBoolMask

List.FilterByBoolMask(List0,mask)
List.FilterByBoolMask({1,2,3,4},{true,false,false,true})

In this way you will have a list with two sublists. Separate sublists will doesn't work with classic code. You need a little trick. Create a list of a given list, then return a flatten list with one less sublist.
ListFBBM = List.Flatten({List0},1);
ListFBBM_in = ListFBBM[0];
ListFBBM_out = ListFBBM[1];

Or use the following method:
ListFBBM_in = __TryGetValueFromNestedDictionaries(ListFBBM, "in");
ListFBBM_out = __TryGetValueFromNestedDictionaries(ListFBBM, "out");