Grimmer, who has had two previous stays at the League One club, is in the final year of his contract at Fulham.
The 22-year-old Scot played seven times on loan in 2014, before helping the club stay in League One last term.
Ebanks-Blake, 30, has scored 10 goals in 33 League One games for the Spireites since signing in June 2015.
The former Manchester United trainee has had spells with six clubs, including Plymouth and Wolves, where he found the net 64 times in 193 appearances.
Grimmer provided one of the highlights of Town's 2015-16 season when he scored in the ninth minute of injury time to beat Sheffield Wednesday in the FA Cup and earn a fifth-round tie against Manchester United.
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Shrewsbury Town have signed Fulham defender Jack Grimmer on a season-long loan and Chesterfield striker Sylvan Ebanks-Blake until January.