A discipline does not get finished in one place and then shipped unchanged to be applied elsewhere. It is worked out again wherever it lands, as local thinkers blend it with their own concepts, so the result agrees with the original in some ways and departs from it in others. The founding theory itself was built the same way, across human difference.
When a foreign theory is rendered with words from an older native tradition, those words carry their earlier meanings into the new idea. A term chosen for 'the unconscious' could still mean a place where God shows himself, and the word chosen for 'self' kept a spiritual core inside it. The imported concept quietly becomes something its originators never meant.
An imported theory need not push out an older tradition; it can bring that tradition back to life. When a new language of sexual drive arrived, readers found matching ideas in centuries-old writing on desire, the appetites, and raising children well, and read those texts with fresh interest.
The supposed signs of the modern self, an inner life and self-rule, did not replace the older picture of a self shaped by duty to God and moral training. Thinkers built a self that was at once self-making and properly formed by inherited ethical knowledge. So the split between 'modern' and 'traditional' selves breaks down.