C:>sqlplus system/passwd@exampledb
C:>create directory DUMPS as '\storagedir';
C:>exit
C:>impdp system/passwd@exampledb directory=DUMPS dumpfile=example.dmp logfile=example-imp.log
... just works as expected

c:>impdp system/passwd@exampledb directory=DUMPS dumpfile=example.dmp logfile=example-imp.log

Connected to: Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production
ORA-39001: invalid argument value
ORA-39000: bad dump file specification
ORA-39155: error expanding dump file name "\storagedirexample.dmp"
ORA-48128: opening of a symbolic link is disallowed