The problem seems to have reported in pieces with barely any answer. It’s not possible to use local wildcards in any form inside a macro. The wildcard will not update and will keep it’s “wild” form even when connected to something else, creating errors when you try to compile, it’s been like that for a very long while and I’m surprised it hasn’t been mentioned more than that so far.
i’ve been having the same problem for a long time, every time i started PIE a warning appeared about an unspecified BP not being compiled but the game ran/packaged fine otherwise.
in 4.19 every BP containing a macro/function with a wildcard won’t compile saying: ‘‘The type of Target Array is undetermined. Connect something to Length to imply a specific type.’’ in this case the ‘‘Target Array’’ is the wildcard array and its length is not accessible
making a new function/macro library didn’t help BUT i’ve tried this in a newer project and it works as it should.