If they are your own branded electronics and you don’t have a WEE number, then it sounds like your products are not fit to be sold in the EU yet.
Electronics come with a variety of safety regulations that have to be met. There are numerous agencies which you can hire in the EU to make your listings compliant.
If your electronics already have CE, that’s a good start but to sell in the EU (including Amazon.de) you also need WEEE registration for each country you sell in. Amazon will eventually block your listings without it.
As a UK company you can still sell in the EU. You just need:
EU WEEE number (Germany requires EAR registration).
An Authorized Representative (AR) if your product needs one.
EU-compliant labeling (CE + WEEE bin symbol + manufacturer address).
Once you have WEEE, you can list on Amazon.de normally.
If you want, I can outline the exact steps for Germany in 1–2 minutes.