These shipwrecks are protected by the laws of many countries.

Like this:

https://www.tripsavvy.com/titanic-wreck-expedition-5088082

How is taking metal or anything else from any shipwrecks in international waters…illegal?

As matter fact done all the time for the non radiation contaminated metals for science and medical research.

it’s a warship..doesn’t make it a holy site…all shipwrecks are graveyards….like the titanic…soldiers get special treatment??

The laws of the sea are not 100% clear, but the wrecks HMS Hood and HMS Repulse are recognized as protected by law as military graves and as culturally significant sites.

This kind of looting has been happening for years. Looters getting caught is the exception here.

which is why Malaysia detained them. it's about 110 km east of the Malaysian mainland: https://en.wikipedia.org/wiki/Sinking_of_Prince_of_Wales_and_Repulse

There is a UN convention against commercial exploitation of "cultural heritage" wrecks: https://www.unesco.org/en/node/79719 , which does cover the Titanic: https://www.npr.org/2020/01/21/798168753/titanic-wreckage-now-protected-under-u-s-u-k-deal-that-was-nearly-sunk

War hulk is cultural? How?

War made these graveyards, if anyone wants to put a peace memorial buoy in the area, that’s ok.

But if you think if makes you look "edgy", you're wrong. Just read something about how people feel about the bodies of their predecessors, if you are unaware of human society.