STMS - centralize transport layer

Hi Guys,

Currently, we have an issue in transports in STMS. We have the below landscapes for project and BAU:

DV1 --> QV1 -->

DV2 --> QV2 --> PV1

Project have 2 transport layers ZDV1 (custom) and SAP (standard)

BAU have 2 transport layers as well ZDV2 (custom) and SAP (standard)

The issue is that we want to import TRs that came from DV1 to QV2 but we got an issue because the transport layer is ZDV2.

1. Is there a way to centralize a transport layer? DV1 TRs can be imported to QV2 without doing it manually.

2. What will be the impact if there's any?

Thank in Advance...