Is it possible to increase the visitor announcement volume on the Google Speakers separately?
1) To pick and choose which device can act as the chime
2) A way to increase the visitor announcement volume without having to increase the device volume
1) You can turn notifications on/off for any device that you don't want the announcement on. Open the Google Home App, find the device and open it. Choose Settings (the gear icon at the top right) > Notifications & digital wellbeing > Do not disturb, then turn on the Do not disturb setting. This will prevent the announcements on that device.
2) I don't think you can control the volume separately. (At least I'm not aware of a way)