How can I find out that a publication has "replicated schema changes" enabled? Where can I find out (preferably using T-SQL) within a published databases, if it would replicate the schema changes?

here is how to create a publication

This topic describes how to create a publication in SQL Server 2014 by using SQL Server Management Studio, Transact-SQL, or Replication Management Objects (RMO).

Replicate Schema Changes
Run this stored procedure at the Publisher:

sp_helpmergepublication


And check this column:

replicate_ddl


A value of 1 means that schema changes are replicated