That add on has been broken for months now.  I haven 't heard of any attempt to fix it.

Try Q Translate:

https://quest-app.appspot.com/

It is relatively accessible.

Hello dear list.
I recently downloaded and installed an add-on for NVDA called
InstantTranslate; but it doesn't function for me at all.
When I select a text or copy one into clipboard, it only says "blank"
and does not translate anything; although my computer connected to the
internet.
I downloaded version 4.0dev of InstantTranslate from NVDA add-ons webpage.
     Thanks in advance,
     Mohammadreza

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