Transmutation constitutes an even more fundamental change/manipulation of matter than what Magneto does. Magnetic properties of matter are mostly the result of its constituent atoms and molecules having unpaired valence electron spins [a]. This gives rise to atomic/molecular magnetic moments which can then interact with external magnetic fields (such as those of Magneto). Magneto still has to overcome the metallic bonds present in adamantium in order to break it. https://en.wikipedia.org/wiki/Electron_pair https://en.wikipedia.org/wiki/Unpaired_electron https://en.wikipedia.org/wiki/Paramagnetism
In contrast, transmutation involves change in the atomic number of the constituent elements of matter ("nuclear reactions"). This requires fusions/fissions of nuclei, and/or changing protons into neutrons (or vice versa) possibly via electron/positron emission or capture ("beta decay"). Such manipulations would in general require mastery over not only the EM but also the strong and weak forces. Once the atomic nuclei in adamantium have been transformed into, say, helium nuclei the electrons would have no choice but to rearrange around these new nuclei, which would automatically break the metal apart. Thus, as long as adamantium is made of electrons and nuclei, a being capable of transmutation should trivially be able to break/change it. It shouldn't even be any harder than the transmutation of any other material, since the building blocks (electrons, protons, neutrons) are the same. https://en.wikipedia.org/wiki/Atomic_number https://en.wikipedia.org/wiki/Nuclear_reaction https://en.wikipedia.org/wiki/Beta_decay
[a] Matter can also display nuclear paramagnetism (in addition to / instead of electronic paramagnetism) but this is thousands of times weaker than the electronic one, due to the magnetogyric ratio of the electron being thousands of times larger than that of a typical atomic nucleus (i.o.w. an electron is MUCH more "magnetic" than a nucleus). Nevertheless, the phenomenon of nuclear paramagnetism has some important applications, of which the magnetic resonance imaging (MRI) used in the hospitals is probably the most well-known one. https://en.wikipedia.org/wiki/Gyromagnetic_ratio https://en.wikipedia.org/wiki/Nucle...ce_spectroscopy https://en.wikipedia.org/wiki/Magne...sonance_imaging
I don't know what it is that you think you "get" but I'm at a lost to know what homosexuality has to do with my thread or anything else here, you are barking up the wrong tree.