Could Germany replace the ships lost off Norway?

Would Germany start building replacement capital ships after the Norwegian losses?

No; Germany was already straining to complete Tirpitz, and losing Swedish ore and Norwegian aluminium makes replacement construction unrealistic.

German yards already struggled to finish Tirpitz even with historical Scandinavian supplies. A Norwegian defeat would remove much Swedish ore and Norwegian aluminium just as Germany lost major hulls and trained personnel. Starting replacement capital ships would therefore compete with completing existing construction and wider armaments needs. Replacement Scharnhorst-type ships are not a credible response to the losses in this scenario.