-Ish I guess :)

Uns ist in alten mæren wunders vil geseit
von helden lobebæren, von grôzer arebeit,
von freuden, hôchgezîten, von weinen und von klagen,
von küener recken strîten muget ír nu wunder hœren sagen

A "mær" (as Maer - imagine an a umlaut) does exist still but the word is so antiquated that I don't expect kids these days to know it. "wunders"? No idea. Something about "wonder"? "vil" sure, viel (a lot). "geseit". No idea. "seit" is that "sein" (to be)? Doesn't fit the rest of the sentence I guess. Definitely need to look that up.

"lobebæren". No damn idea whatsoever. Now "grôzer arebeit", sure that's "grosser Arbeit" but when I look at the "translation to German" (from the middle high German the original apparently is written in) it says it's "groesse Muehsahl". Close enough of course. Kind of like translating French word for word into German. It sort of makes sense but is just hopelessly old and weirdly structured but you can understand a lot of it. But it requires lots of brain power. Nothing that I can do while listening/talking, only while reading.

"hôchgezîten": Hochzeiten? Like weddings? Makes no sense. Maybe "Hochzeiten" as in 'high times'? Funnily same word different pronunciation depending on context :)

"recken" very old word. Again something kids these days probably have no idea about. I do but it's been a while I learned it all. "strîten" means streiten I guess which makes sense given the Recken, but without knowing what those are, not sure. "muget" Sounds like "muggle" but maybe "moeget"? So "moegte ihr". "nu wunder hœren sagen": "jetzt wunder hoeren sagen"? But what does that mean?

Some of this may not be a problem of "Shakespeare's times" vs. today but also "poem language" vs. "regular people language". I have trouble with poems.

I'd write it as this basically:

Uns ist in alten Maeren viel Wunder <no idea what geseit is>
von Helden <somethingwhatever>, von grosser Arbeit
von Freuden, Hochzeiten, von Weinen und von Klagen,
von kuehner Recken streiten moeget ihr Wunder hoeren sagen

Now even after looking up the two missing words, geseit is gesagt (to say) and lobebaeren just doesn't exist but was somehow translated to something I still would not be able to understand this if it was just read to me. I have to read it myself and actively think about it. On the other hand my sibling posts meandering whole paragraph sentence is very easily understandable.

On the other hand, here's a recipe for strengthening a wooden shield with leather in old English:

take lether that ys half tannyd and drye hym and shave the flesshe syd
and take glwu wt water and set yt over the fyere
and melte yt wt water and then al hote ly yt a pone the leder on the flesshe syde
and strawe ther on the powder of glasce bete yn a brasene morter ...

I'll stop there so we stay within the same 4 lines. But I had a much easier time reading that than the Niebelungenlied. And yes, my mother tongue is German :)

take leather that is half tanned and dry him and shave the flesh side
and take glue with water and set it over the fire
and melt it with water and then while hot lie it upon the leather on the flesh side
and strew thereon the powder of glass beaten in a <brasene I had to look up but also makes sense: brass-en> mortar

If anything, except for spelling mistakes like syd vs. syde, I think that's actually more consistent than modern English. I.e. I'd say syd for side is perfect. A y by itself makes the "why" sound. So syd is exactly how I'd write it if I was told to write it just from hearing the word once and knowing the alphabet. Why does it need an e at the end and why would we nowadays write it as side but not pronounce the e (like French sort of, just leave out the last 1-3 letters when pronouncing a word).