Is the electrical cable properly insulated?

Hello,

due to an error, the sockets had to be moved about 50 cm to the left,
I am a bit skeptical whether this was done properly,
to me it looks quite amateurish, as far as I know, cables inside plaster must be double insulated or a junction box must be used, the electrician said everything was done professionally but you often hear such statements on construction sites and 80% of the time it is still wrong, just take a look at the pictures.

thanks in advance

How were the individual wires connected? You only see something red, which could be a splice connector. And a lot of insulating tape, which looks very sloppy. Junction box terminals could have been used.

Hello,

do I understand correctly that the 3 boxes on the right will be plastered over and the three boxes on the left will be used instead?
At the same time, because the power is only available there, the "old" boxes are used as connection points?

If that is the case, this is a violation of DIN VDE. All connection points must be accessible, e.g., under a socket or a blank cover.

The way your electrician realized the connection point, with the insulating tape, seems very amateurish.
Connection terminals are used for this, e.g., Wago 2273 or 273.

Suggestion:
The three boxes on the right are not plastered over but are also equipped with sockets.
The pure material cost for a conventional socket insert + frame is about €5 (!).

that's how it looks, the right side is closed off and the left side remains, in the third picture you can see clamps or whatever that is, I already knew that even though I am a layman, connections must always be accessible