Why don't you rewrite the subroutine to take named parameters as a hash like so?

sub func {
  my %args = (
    # default options
    option1 => "Foo",
    option2 => "Bar",
    @_, # passed options
  );
  if ($args{option1}) { ... }
  if ($args{option2}) { ... }
}

func(option1 => "Foozball", option2 => "Barracuda");
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