What does excessive eye blinking and nose scrunching in a child with a severe abuse history indicate?

Tic. Could be a nervous tic. Could also indicate some anxiety. Talk with your child's pediatrician to determine the cause.
Tics. Tics are repetitive behaviors that do not serve a physiologic purpose. Years ago they were often called "nervous tics" as they were thought to be primarily a manifestation of anxiety. While that can occasionally be true, the majority of tics occurring during childhood are now thought to be random events without a known cause. Up to 5% of children will have a transient (weeks-months) tic.