Originally Posted by LapLap

The large cruise ships will moor at the pier closest to the Port Terminal Station (Pier Number 4) and the Onsen Ren is on Pier Number 1 (roughly 10 minutes apart on foot)

There will be large Cruise ships arriving or departing on close to 100 out of 365 days next year. There will be days when more than one large ship is there at a time, perhaps those are the days you might want to avoid.
You can cross check your proposed dates on this or similar resources: https://www.cruisetimetables.com/kob...dule-2026.html