Here’s my translation
Quite difficult in places! 😊
Alan
2. Frá ætt Hrafns.
2. About Hrafn‘s pedigree.
Sveinbjörn hét maðr, sonr Bárðar svarta, Atlasonar, Höskuldssonar, Atlasonar, Högnasonar ins heppna, Geirþjófssonar, er nam Geirþjófsfjörð, Valþjófssonar ins gamla.
[There] was a man called Sveinbjörn, son of Bárðr [the] black, son of Atli, son of Höskuldr, son of Atli, son of Högni the lucky (heppinn), son of Geirþjófr, who took-[possession-of] Geirþjófsfjörðr (Geirþjófr’s-fjord), son of Valþjófr [the] old.
Sveinbjörn bjó í Arnarfirði á þeim bæ, er á Eyri heitir.
Sveinbjörn lived in Arnarfjörðr (Arni’s-fjord) on that farm, which is-called ‘in Eyri’ (in Sand-bank).
Hann átti konu þá, er Steinunn hét.
He had [in marriage] that woman, who was-called Steinunn.
Hon var Þórðardóttir, Oddleifssonar.
She was [the] daughter of Þórðr, son of Oddleifr.
Sveinbjörn var goðorðsmaðr ok vitr, ok mikill atferðarmaðr, læknir góðr.
Sveinbjörn was a man-with-the-dignity-and-authority of a goði (heathen priest-chief) and wise, and a great man-of-energy, [and] a good physician.
Atli, föðurfaðir hans hafði verit með Magnúsi konungi inum góða Óláfssyni í bardaga á Hlýrskógsheiði, þá er hann barðist við Vindi.
Atli, his father’s-father (paternal grandfather) had been with King Magnúss the good, son of Ólafr, in [the] battle of (lit: on) Hlýrskógsheiðr (Bow’s or Cheek’s?-forest’s-heath) (Lyrskovshede, South Jutland, 1043 AD), when he fought against [the] Vindir (= <Vindr>, CV, ie the people of Vindland, the Wends).
Þá vitraðist Óláfr konungr Magnúsi, syni sínum, bað hann velja tólf menn af öllum herinum, þá er væri af inum beztum ættum, til þess at þeir bindi sár manna.
Then King Ólafr appeared-in-a-vision to Magnúss, his son, bade him to choose twelve persons (men) from all the-army, those who were of the best pedigrees, to that [end] (ie for that purpose) that they would-bind [the] wounds (acc neut pl) of persons (men) (gen masc plural).
En hann kveðst þat þiggja mundu af guði, at í hvers þeira kyni skyldi síðan lækning haldast, er þar væri til valdir sár manna at binda.
But (and) he (ie Magnúss) declared-of-himself [that he] would (<mundu> is past infinitive) receive that [(presumably) as a gift?] from God, (so) that after-that (ie thereafter) [the] healing-art (<lækning>, Z3) should be-maintained (ie continue on, be passed down, <haldast>, Z.iv) in [the] kin (dative) of each of those (genitive) (ie the twelve), who were chosen (<valdir> = nom masc pl pp of <velja>) to bind [the] wounds of persons (men).
En eftir bardagann skipaði hann þeim til at binda sár manna, því at fáir váru læknar í liði hans, en menn váru margir sárir orðnir.
But (And) after the-battle he assigned (<skipa>, Z3) them to bind [the] wounds of persons (men), because few (men) were physicians (plural of <læknir>) in his troops, but many persons (men) were become (ie had been) wounded (adj).
Þar batt Atli sár manna fyrsta sinn at boðorði Magnúss konungs ok var síðan algerr læknir sem allir þeir, er þar bundu sár manna.
There Atli bound [the] wounds of persons (men) (plural, as above) [for the] first time (<sinn>) at [the] bidding of King Magnúss and after-that was a perfect (‘fully qualified’) doctor like all those, who there bound [the] wounds of persons (men) (plural, as above).
Svá kom lækning af guðs miskunn fyrsta sinn í kyn Bárðar svarta.
Thus [the] healing-art by (lit: from) [the] grace of God [for the] first time (<sinn>) came into (ie was introduced to) [the] kin of Bárðr [the] black.