I have often said that human language is the greatest stumbling block that we, as a species, have in trying to understand anything fundamental about the world we live in. You may have a sudden brilliant insight; the moment you try to articulate it, it's either gone or you find that it cannot be articulated. Language does not enhance understanding. On the contrary, it derails understanding. Perhaps this is why the great sages of the past were more likely to speak in parables, to offer analogies, rather than to describe something directly.
Recall Lao-Tzu's famous dictum: "Those who know, do not say. Those who say, do not know."
There's a story about a Zen master who was asked by his students what those words meant. He thought for a moment, then said, "Do you know the fragrance of a rose?" They all said yes. "Describe it in words for me," said the master. The class was silent.
I doubt very much that your idea of a universal language of metaphysics could ever be realized. It's a quite different matter with mathematics or the so-called "hard" sciences. These disciplines deal only with apparent
reality. Metaphysics deals with ultimate