Some years ago I had a electrum wallet when I used to use BTC to buy weed over the darknet (yep) in a HDD. Shit happens, that HDD got formatted to install again Win. I didnt take care much back then, but as you can imagine with the recent BTC rises I tried to restore files from that HDD, and I've been able to recover some related files
Formatting your hard drive doesn't erase data, it just marks the space to be reused.
If you did re-use that space, the chances of your recovering the data without
spending obscene amounts of $, is almost zero.
(I say
almost zero because there is a reason wiping programs erase and rewrite a sector multiple times)