Hello and welcome, the texts you are looking for can be found at 0x019422
in this case I found them doing a visual search.
Taking as reference the PPU Viewer data, to know where the graphics of that text are located.
Another equally valid method is comparing some version previously translated into any language and the original ROM.
Even if you can't find another way out, you can discover what you are looking for by overwriting small portions of the ROM code in real time through the hex editor built into FCEUX.
In this way, it would only be necessary to restart the game to see how it is affected, and undo the changes that block the game (of course), until what you want to find is the only thing that fails.
I don't know if these are the best tips, but I hope you find them useful, good luck