Hey, everyone! For a long time I tried to find such way of sync. And there was an old feature request about that, which was closed as "not enough votes" https://community.spotify.com/t5/Closed-Ideas/Last-fm-Sync-last-fm-loved-Tracks/idi-p/274574
So I made small sync tool for it by myself. If you've ever struggled with liking songs twice (once on Spotify then on Lastfm) then here is solution
Hope you will enjoy it!