Green’s Dictionary of Slang

shifting adj.

(UK Und.) cheating, larcenous; occas as n.

1615		Merrie Dialogue Between Band, Cuffe, and Ruffe B2: cuffe: He is a most filthy Snivelling fellow, [i.e. a lawyer] and he will wipe your Nose of all, if you put the case to him. [...] ruffe: He is a shifting knave, and one to whom Band, a little before had beene much beholding.
1859		Matsell Vocabulum 79: shifting Cheating or stealing.

In compounds

shifting cove (n.) [cove n. (1)]

(UK Und.) a confidence trickster.

1811		Lex. Balatronicum n.p.: Shifting cove; i.e. a person who lives by tricking.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.