Hello Experts, Is there anyway we can use transaction currency different than the subsidiary's base currency for interCompany PO and SO?

Just add the desired currency to Vendor and Customer record. Note you do need to add currency to list>accounting>currency>new

yes, you can. However, it will be the same currency for both PO and SO if you use Manage IC SOs functionality. On another token, you do not have to use POs and SOs at all, just invoices and VBs and you can use any currency, but then there is no linkage between the two transactions > IC reconciliation will suck

@Sam-I-Am currencies are already added in vendor and customer but can not user currency other than the subsidiary's base currency for inteCompanny POs and SOs.

enable multi currency - Setup > Company > Setup Tasks > Enable Features>company tab> Multi currency