According to MS documentation

https://learn.microsoft.com/en-us/dynamics365/fin-ops-core/dev-itpro/data-entities/dual-write/dual-write-system-req

Dual-write has these limitations:

• You can't run dual-write and the Prospect to cash solution for Data integrator side by side. If you're running the Prospect to cash solution for Data integrator, you must uninstall it.
• Dual-write setup is not supported on trial instances of finance and operations apps.
• Dual-write must be used to integrate a single finance and operations app instance and a single customer engagement app instance.
• Dual-write currently has an initial synchronization limit of 40 legal entities.
• Dual-write live synchronization has a limit of 250 legal entities.
• Dual-write does not support cross-company data sharing.
• Dual-write requires that the finance and operations app and the customer engagement app must be in the same Microsoft Azure Active Directory (Azure AD) tenant.
• Dual-write requires that the finance and operations app and the customer engagement app must be deployed in the same Microsoft Azure data center.
• Dual-write is not triggered by the doInsert, doUpdate, and doDelete events of finance and operations apps. Use the Insert, Update, and Delete events in finance and operations apps when you want to trigger dual-write.
• Dual-write doesn't support distributed transactions. For example, if the product receipt posting process is canceled, dual-write might create the product receipt in Dataverse but not create it in Supply Chain Management.

If the new dual write solutions need the cross-company data sharing to be disabled then users should receive a message notification or warning in Finance &Operations. We suggest a message telling users that dual-write solutions need cross-company data sharing to be disabled.