Advice wiring up Ezviz DB1C video doorbell with Byron chime and transformer

[itm]

I have an Ezviz DB1C smart video doorbell, and have bought a Byron 776 chime to go with it, as it was on the compatibility list for the DB1C (Compatibility List for DB1 & DB1C Chime - FAQ - EZVIZ Support).
The Byron has an internal 8V transformer, but Ezviz have advised that the DB1C needs a 16-24V supply to power it.
If I follow the instructions for connecting the DB1C power kit to the chime (see image below) then presumably the DB1C will draw its power from the Byron's internal 8V supply.
Could anyone advise:
1. How I would integrate a separate 16-24V supply into this setup - i.e. how should the wiring be done between the DB1C, the DB1C power kit, the transformer and the Byron chime? ...and
2. If I went for this model from Screwfix, could I plug it into a normal 3-pin socket with a 3-amp fused plug? - British General Fortress 8-24V AC 8VA Bell Transformer Module (I'm trying to avoid the expense of having an electrician doing the fitting - I currently have the DB1C running from a 12V DC 1A transformer, and it works fine, but I guess I need more power to support operation with an external chime).

 

[itm]

The instructions from Ezviz are to make the connections as per the attached diagram. If the chime has an internal 8V transformer (and is also connected to the 240V mains supply) would this cause a problem?

 

[Zedmeister]

You do know that Ezviz do a plug in chime now, that does not need an electrician?

 

[itm]

You do know that Ezviz do a plug in chime now, that does not need an electrician?

Yes - I have it but it's much too quiet. We can't hear it upstairs!

 

[sebastiantombs]

@itm Maybe get a second one for upstairs?

 

[itm]

@itm Maybe get a second one for upstairs?

It's a large 3-storey house and the chime is virtually inaudible in most of the house. I'd need to spend about £250 to get adequate coverage for the whole house!