Hello,
I'm not sure that adding 500 buttons to a sheet is a good idea. You could set up a SelectionChange event that monitors if a cell is clicked. The visible words are in column A, the translations are in column B and formatted with custom format ";;;" - which will effectively hide them. With the macro below, you can click on the original word to show the translation in column B. Then click on the translation in column B to hide it again. If you click anywhere outside column A, all translations will be hidden.
See attached file for a working example.
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