This group will become a problem for Afghanistan and Tajikistan as all the Tajik militants will rally around it. It will also become a problem for China as well as Sinkiang is a short distance from Badakhshan. The oil and gas pipelines will be in danger as well as road transport and future railway line discussed elsewhere in this forum. It should be noted that Khorasan is a name used by the ISIS in the past. This looks an extremely short sighted knee-jerk reaction project with major negative consequences. If my plan for One Confederation - Two Systems with Afghanistan having Sharia System and us having Democracy is adopted then the problem would be nipped at the source. TTP would not have any reason to create problems in Pakistan as Sharia can be introduced by vote gradually just like the previous Nizam-i-Adl in Swat and Afghan Taliban can also be modernized gradually. Remove the customs duties and have a Defence pact instead of destroying each other through proxies. As noted in the Pak Army Strategy, this is a time for Geo-Economics and to work on a union model just like the EU.
In that case Pakistan shouldn't because we shouldn't support such organization but anything that is counter Afghan Taliban should be promoted to always keep them in check.