Since you mentioned Wemos D1, I suggest you have a look at their website. https://www.wemos.cc/
They have Boards, and shields. https://wiki.wemos.cc/products:d1_mini_shields
https://wiki.wemos.cc/products:d1:d1_mini.
In the end though I think you would be better off understanding all the components you need, and coming up with a more “custom” solution. If you go the shield route you may end up sticking your fingers near the relays when pressing buttons and such.
Also, searching this site for thermostat yields quite a few results.
https://community.blynk.cc/search?q=thermostat
Maybe this can lead you to a starting point that you could easily expand on. Possibly this one: