The -cp option expect a private key in hex format:
pons@linpons:~/VanitySearch$ ./VanitySearch -cp 5B3F38AF935A3640D158E871CE6E9666DB862636383386EE510F18CCC3BD72EB
PubKey: 03BB113592002132E6EF387C3AEBC04667670D4CD40B2103C7D0EE4969E9FF56E4
Addr (P2PKH): 12csaq6uhAtyhzUN8N4akVpat7GP6wB3ea
Addr (P2SH): 34rLuX6QStr8qJCbmWouBuVQGDrFT4h453
Addr (BECH32): bc1qz8qw3se7c8rr7vs6sgnp29xv2vsutamxyd839p
There is no trivial way to do what you want with VanitySearch, you can write a small script:
pons@linpons:~/VanitySearch$ cat tst.txt
5B3F38AF935A3640D158E871CE6E9666DB862636383386EE510F18CCC3BD72EB
5B3F38AF935A3640D158E871CE6E9666DB862636383386EE510F18CCC3BD72EC
5B3F38AF935A3640D158E871CE6E9666DB862636383386EE510F18CCC3BD72ED
pons@linpons:~/VanitySearch$ for i in `more tst.txt`; do ./VanitySearch -cp $i | grep Addr | grep P2PKH | awk '{ print $3 }'; done
12csaq6uhAtyhzUN8N4akVpat7GP6wB3ea
1PGVt2mWHgbULrx9pjWDPc2EKp2LWLT4fd
1DVjd5oZqCCYywtgL7FLbT3ZX4FFJK5nwc