> Helgi af Skeiði var og þar og eggjar þá fast og kvað nú
> vel að þeir Bolli reyndu hvort honum væri kapp sitt og
> metnaður einhlítt eða hvort nokkurir menn norður þar mundu
> þora að halda til móts við hann.

> Helgi from Skeidi was also there and (he) then eggs them
> on firmly and said now well that they, Bolli (et al),
> proved whether to him would be adequate his zeal and pride
> or if some northern men would there dare to march against
> him. (Z. mót 4 - halda til móts við e-n = to march against
> one)

> Helgi from Skeið was also there and urges them firmly and
> declared (it) now well that they, Bolli (and he) tested
> whether his (Bolli´s) eagerness and ambition were
> sufficient for him (?) (whether Bolli was up for the fight
> with him) or whether some persons (men) there in (the)
> north would dare to stand (or march) against him.

I think that you’re right in assigning <honum> to Helgi.
(Side note: <og metnaður> is sort of parenthetical, since
<einhlítt>, being neuter, must technically go with <kapp>.)

> Hann ríður upp á Völlu til Ljóts og þegar þeir finnast
> mælti Óttar: "Eigi er nú setuefni Ljótur," sagði hann, "og
> fylg þú nú virðing þinni er þér liggur laus fyrir."

> He rides up to Vollu to Ljot and at once they, Ottar (and
> he) meet to speak: “(There) is now no basis of agreement,
> Ljot,” he said, “and follow now your honor than you wait
> in empty ambush.”

> He rides up to Vellir to Ljótr and as-soon-as they
> meet-one-another Óttar spoke: “Now (there) is not a
> situation-for-sitting (ie this is no time for being
> idle?), Ljótr,” he said, “and pursue (imperative) (you)
> now your honour which lies loose (free, available) before
> you (ie for which the opportunity now exists?)”

That’s pretty much my reading: ‘this is no time to
rest/relax’, and ‘your honor/reputation is there for the
taking’.

> Ljótur mælti: "Oft sýnir þú af þér mikinn drengskap."

> Ljotr said: “You often show for yourself much
> high-mindedness.”

> Ljótr spoke: “Often (opt) you show of yourself great
> high-mindedness (or courage?).”

High-mindedness seems to fit the context better.

> Þeir Ljótur ganga fram í meðal þeirra snarlega svo að þeir
> máttu nær ekki að hafast.

> They, Ljotr (et al), quickly intercede as their
> peacemakers so that they could not nearly abide (?).

> They, Ljótr (and co) go forward (on foot) in between them
> quickly so that they (ie the combatants) might not
> have-themselves near (to each other).

I think that this is <hafast at> 'to do': ‘so that they
could do almost nothing’.

> Vil eg einn gera milli yðvar um þessi mál en ef því níta
> aðrir hvorir þá skulum vér veita þeim atgöngu."

> I want alone to arbitrate between you, and if it refuses
> (“it is refused”?) by the other, then we will help them
> attack.”

> I want alone to arbitrate between you concerning this case
> but if each other (of the parties) refuse that then we
> shall make an assault on them.”

I would make ‘and if one or other of the two refuses that,
then ...’; see <annarr hvárr> in Z.

Brian