Upvote:2
Transit aside, concerning Switzerland, there is an entry ban in place for people coming from UK for short-stay purposes. Only nationals of Switzerland or Liechtenstein (or their family members), as well as residents of Switzerland, are permitted to enter Swiss territory. Even though in practice this might not be enforceable if you self-transit in another Schengen country, but legally you are not exempt just because you are transiting through France.
You will also be required to self-isolate for 10 days upon entry.
Upvote:4
At the present time, entry into France is restricted.
You are allowed to enter France from the UK to go to Switzerland only if:
There are a few other possible reasons but they are quite specific.
So, in your case, since you are a EU citizen, you are only allowed to cross France to go to Switzerland if you are a Swiss resident (or if you also hold Swiss citizenship, or are French).
In addition to the conditions, as you are arriving from the UK, you need to:
All documents and additional details are available here.
Once you fulfil all those conditions, you can indeed stay overnight while on your way. You should however note that lots of hotels are currently closed, all restaurants and bars are closed, and wearing a face mask is compulsory indoors (except in your room) and in many places outdoors as well. You are also not allowed outside between 8 pm and 6 am (curfew in place).
Note that all these requirements are the same whether you stay overnight or not.
Note also that current Tier 3 and 4 restrictions in the UK may also prevent you from travelling, and there may also be additional restrictions for Switzerland: I only covered the requirements to enter France for transit.