These Links might help you:

Replication Partners and schedule replication

http://www.symantec.com/business/support/index?page=content&id=TECH104986&actp=search&viewlocale=en_US&searchid=1320763548914

We have a 2 SEPM Servers one in local and one in remote location, Just need to enable the replication  like below

1. I just want reporting remote clients from there coming to the local server, and of course to be able to manage updates for them if required,

you can configure Managment priority list for this.

1. I don’t want local clients report to remote server.

the clients will reflect in both SEPM, if the replication ios enabled

1. I just need to enable the 1 way replication. Is it possible?

logs , clients and packages can be configured for 1 way. Others like groups, clients and policies will be both way.

Could anyone please explain , how to enable the one way replication?

you have to uncheck the fields for logs or clients package or content in the replication settings and it's direction.