how can someone else also get the bow in der eisendrache

Yes—another player can get a bow in Der Eisendrache if the bow has already been picked up and then put back, or if the team is using the bow-duplication glitch people discuss in co-op. Reddit players also mention that after completing a bow upgrade, you can pick it up, swap it, and let someone else grab the bow from the altar/quest location again.

Normal co-op method

• One player completes the bow upgrade.
• They then drop or swap that bow so it returns to its altar spot.
• Another player can then pick it up and continue their own upgrade path.

Shared-bow edge cases

• Some players say that if someone already has the bow equipped, another player can still obtain it through certain revive or Mule Kick interactions.

• There are also reports of duplication using Near Death Experience, Phoenix Up, or Arms Grace in co-op, but those are glitch-based and not the standard intended method.

Practical note

If your goal is just for a teammate to also have a bow, the cleanest route is to finish one bow, put it back, and let the next player pick it up.

TL;DR: In normal play, one person can make the bow available again by swapping it back at the altar so another player can grab it; true “double bow” setups usually rely on glitches.