FOVAL Power Step Down 220V to 110V Voltage Converter looks like really the best choice, but it is rated to 230W max. Check the max rating of the stuff you need to plug in it, and then look for something similar. It also comes with a EU compatible cable, so you no longer need the Plug Convert to 2-pin EU
EDIT: strangely enough, ANKER products sold in the EU all seem to support dual voltage, see Anker PowerPort Atom III Slim Wall Charger, Dual USB-C Ports (65W Max) or Anker 735 Charger (GaNPrime 65W) USB-C Charger,
Advice: if you have the time, and the possibility, return your US devices, and get the EU, dual voltage, version or equivalent - this way, you'll be able to use them anywhere you are, with just some passive plug adapters.
Yes you need both an adapter (link 1) and a converter (link 2). Hopefully you have noticed that the input and output voltage of the adapter is the same, so without series connection of adapter of transformer; boom.
/e I just reviewed the link and noticed that if you buy the Voltage-Converter you do not necessarily, need to buy an adapter. It looks the necessary power cord (for Germany) is included. That particular transformer on the other side is total bull. You would need to buy an adapter and a power cord for the socket or the transformer, depending on the adapter for the input alone. I think it's designed for countries with similar sockets but different voltage like us <-> aus.