i Register
In some senses, unwieldy is marked as obsolete. Watch for register when choosing this word.
adj
Lacking strength; weak.
Ungraceful in movement.
Difficult to carry, handle, manage or operate because of its size, weight, shape or complexity.
She is popular with passengers as an all-weather vessel, but rather the reverse with yachtsmen as she has at times proved somewhat unwieldy, and certainly takes up a good deal of space in the narrow channels.
However, the constellation of Argo Navis was so huge and unwieldy that in the 1932 revision, the International Astronomical Union committee chopped it up into a keel (Carina), a poop (Puppis) and sails (Vela).
Badly managed or operated.