As a native German speaker, I can at least say that knowing both German and English doesn't really help in understanding the text. Not even the most "dumbed down" version - ok, he's apparently saying something about his wife, but no idea what exactly. And when I read "shyne (Modern English "sheen" but German cognate is closer)", I was even more confused. "Sheen" is the property of an object that is shiny, which in German would be "Schein", but because it is applied to a woman, I assume that the "cognate" he refers to is "schön" (beautiful)?
Another Modern English cognate even closer to shyne than "sheen" is "shine" (and obviously the German "schein"). The words for "beautiful", "fair", "bright", "shining", "well-reputed", "righteous" have a long history of being related:
Highly dependent on passage and writer imo, for anything before 1500
Some people I've had say middle english is easy enough to read now, and that's sometimes true, but if you drop some passages of Gawain or Pearl in front of people they'll be convinced it's an extra 2-300 years older. Anything non-London dialect is harder
https://en.wiktionary.org/wiki/schinen#Middle_English (to shine, to appear)
https://en.wiktionary.org/wiki/skyr#Middle_English (clear-coloured, pale, light, luminous, radiant)
https://en.wiktionary.org/wiki/sciene#Old_English (beautiful, fair, brilliant, shining)
https://en.wiktionary.org/wiki/Reconstruction:Proto-Germanic... skīnaną (to shine, to appear)
https://en.wiktionary.org/wiki/Reconstruction:Proto-Germanic... skīriz (pure, clear, sheer)
https://en.wiktionary.org/wiki/Reconstruction:Proto-Germanic... skauniz (beautiful, shining)
and ultimately the PIE
https://en.wiktionary.org/wiki/Reconstruction:Proto-Indo-Eur... (s)ḱeh₁y- (to shine)
There are cognates absolutely everywhere in modern Germanic languages:
https://en.wiktionary.org/wiki/sk%C3%ADr#Icelandic skír (bright, clear, pure)
https://en.wiktionary.org/wiki/skir#Swedish (sheer, delicate, shining)
And even in Slavic languages:
https://en.wiktionary.org/wiki/Reconstruction:Proto-Slavic/s... sijati (to shine, to illuminate)
Skauniz was even borrowed to Proto-Finnic and highly conserved in modern Finnish, Estonian, Ingric, etc. which all have kaunis meaning "beautiful"!
https://en.wiktionary.org/wiki/Reconstruction:Proto-Finnic/k...
Some people I've had say middle english is easy enough to read now, and that's sometimes true, but if you drop some passages of Gawain or Pearl in front of people they'll be convinced it's an extra 2-300 years older. Anything non-London dialect is harder