Split Lagom Journal during data migration

We have a Lagom 1.4 System in Production, the current architecture uses a Postgres database as the write-side and as part of an optimization exercise, we are looking into the possibility of splitting the database to have an instance for each Lagom service. The read-side is easy to handle, but looking at the journal and snapshots tables, I am assuming I could export the journal table and selectively import the records, each entity set (all shards of an entity) to the appropriate database.
I would then also migrate all relevant snapshots and read-side-offsets to the new database instances.

Downtime is not an issue during the migration, would this work or are there other factors that need to be considered?

any advice would be appreciated.