It looks normal that it no longer works with the route because "/ en /" is missing
You tried to put:
$route['en/page/test'] = 'news/page/1';
or
$route['en/page/test'] = 'en/news/page/1';
(I do not know i18n firmware)
If this works, the solution can be used with a wildcard:
$route['(:any)/page/test'] = "news/page/1";
or
$route['(:any)/page/test'] = "$1/news/page/1";
(again i don't know how plug i18n plug works)
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