Conditional relative clauses that set forth less vividly the realization of a future event take the optative. The main clause has the optative with ἄν.
ὀκνοίην ἂν εἰς τὰ πλοῖα ἐμβαίνειν ἃ (= εἴ τινα)
ἡμῖν Κῦρος δοίη
δ δὲ μὴ ἀγαπῴη, οὐδ' ἂν φιλοῖ
a. The main clause has the optative without ἄν in wishes:
δῶρα θεῶν ἔχοι, ὅττι διδοῖεν
b. Homer sometimes uses κέ or ἄν in the relative clause (φ 161).
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].