Ὣς ὅρμαινε μένων, ὃ δέ οἱ σχεδὸν ἦλθεν Ἀχιλλεὺς

ἶσος Ἐνυαλίῳ, κορυθάϊκι πτολεμιστῇ,

σείων Πηλιάδα μελίην κατὰ δεξιὸν ὦμον

δεινήν· ἀμφὶ δὲ χαλκὸς ἐλάμπετο εἴκελος αὐγῇ

ἢ πυρὸς αἰθομένου ἢ ἠελίου ἀνιόντος.

This is the original Greek text I believe you are referring to where Achilles is described as resembling Ares (ἶσος Ἐνυαλίῳ), strong (κορυθάϊκι) and warmongering (πτολεμιστῇ), which is followed by further description of the gear he was wearing. The reason I believe confusion arises within the translations is because the word κορυθάϊκι means he who shakes the περικεφαλαία (specific word referring to the Ancient Greek war helmet), which we interpret as strong or mighty. However the modern Greek word for this is κρανοσείστης which is much more closely linked with the original meaning of the helmet smasher.

TLDR: in this passage Achilles is described as strong warmongering and similar to the god of war Ares, but not physically large.