Is the app to spy on other people's seed phrases or your own?
If the former is the case then wouldn't advise anyone to engage in an activity like this because it's unethical.

But if it's just to see just to see the seed phrases of accounts opened by you, then I don't see any issue arising.
But I still don't see the use for it since your secret phrase is meant to be stored privately and not to be shared with any online service and you having it displayed on telegram makes it more vulnerable to hacks.