I would like to switch "LOCAL UNDO ON" for our CDB. Does it impact our existing PDBs?

Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production Version 19.14.0.0.0

Our CDB has an UNDO TABLESPACE with name "UNDOTBS1".

LOCAL UNDO is currently OFF.

Our PDBs have been migrated from 11g and have an UNDO TABLESPACE with name "UNDOTBS1" as well. They use they own datafiles.

Can I simply switch undo on connected to the CDB in this fashion:

SHUTDOWN IMMEDIATE;

STARTUP UPGRADE;

ALTER DATABASE LOCAL UNDO ON;

SHUTDOWN IMMEDIATE;

STARTUP;

I would not like to touch our existing PDBs.

Will the PDB's UNDO TABLESPACE still work or does it need a drop and recreation?

Many Thanks,

Uli