Mutliple sources:
Dortmund pluck Soumaïla Coulibaly from PSG Youth Academy
By Peter Vice @ViceytheSS
Borussia Dortmund plan to introduce a new high-profile signing for next season in the coming days.

The 17-year-old will not be procured via a transfer fee as he is being signed off an expiring contract. Coulibaly has not yet made an appearance for the PSG senior team, but has been training with them recently. A late ACL tear was apparently of no concern for the Schwarzgelben, who plan to immediately integrate the teenage into the professional squad once he has healed.
The deal carries with it shades of Dan-Axel Zagadou's acquisition, also from PSG, in 2017. The German club built Zagadou into a €35 million player before his current injury-riddled season.