It is unclear which type of accent Chopin meant here. The sign is shorter from all previous ones on this page of A (bars 289-290); however, its shape is characteristic of long accents – cf. the accent in bar 293. GE (→FE) has a short accent, which in EE was changed to a vertical sign.
Compare the passage in the sources »
category imprint: Graphic ambiguousness; Differences between sources
issues: Long accents, EE revisions
notation: Articulation, Accents, Hairpins