Packet List options are functions that are performed on properties of the packet list, e.g. to reorder the packets.
Reorder Packets by absolute time: when capturing traces using multiple interfaces in tshark/Wireshark/dumpcap it is quite likely that some of the frames will be written to the file out of order. Those are easily spotted by looking at - or filtering for - frames with negative delta times. If this option is selected TraceWrangler will sort the frames by absolute time stamp when writing the file.
Fix frame size meta data: sometimes, frame lengths are stored incorrectly, with the frame size and capture size both set to sliced length (meaning, less bytes were stored to disk than were actually present on the wire). TraceWrangler can try to recalculate the correct wire size by looking at length fields of protocols like IPv4 and IPv6.
Also recalculate wire size when not hard sliced: normally, the meta data fixing process will only fix frames where capture size = wire size. This option forces also fixing frames when both are different, meaning that IP length information will be used in all cases