How to change a public function inside a class of a plugin?

It’s not possible to overwrite the class function without modifying the file (unless your hosting supports some form of “monkey patching” as its called)
you could check if this function “tve_dash_api_remote_get” has a filter in it that allows you to manipulate the uri

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)