So just put the cable directly into the lugs under the 200 amp shut off and run them to the 100 amp panel with the cable sized for the 100 amp right?
Only if the installation starts and terminates outside" NEC 240.21 (B) (5)
"Outside Taps of Unlimited Length. Where the conductors are located outside of a building or structure, except at the point of load termination, and comply with all of the following
conditions:
(1) The tap conductors are protected from physical damage in an approved manner.
(2) The tap conductors terminate at a single circuit breaker or a single set of fuses that limits the load to the ampacity of the tap conductors. This single overcurrent device shall
be permitted to supply any number of additional overcurrent devices on its load side.
(3) The overcurrent device for the tap conductors is an integral part of a disconnecting means or shall be located immediately adjacent thereto.
(4) The disconnecting means for the tap conductors is installed at a readily accessible location complying with one ofthe following:
a. Outside of a building or structure
b. Inside, nearest the point of entrance of the tap
conductors
c. Where installed in accordance with 230.6, nearest the
point of entrance of the tap conductors