Graham Dorrans has signed a two-year deal with Norwich City following a successful loan spell with the club.
Bournemouth have signed their second goalkeeper in two days by acquiring ex-Reading stopper Adam Federici.
APOEL - managed by former Hearts boss Paulo Sergio - are the reigning Cyprus champions, winning many friends and accolades as they made the quarter-finals of the Champions League two seasons ago.
Sheridan, 24, started his career with Celtic before spending time on loan with Motherwell and St Johnstone and he also enjoyed a short spell in Bulgaria with CSKA Sofia.
He moved to Rugby Park at the start of last season, making 28 appearances, scoring 10 times including a hat-trick at Tynecastle in September.