Sale like E-1 , not clear about documents

yes purchase vendor will issue invoice and u will be able to take input credit -igst

u will charge igst output liabilty from uttrakhand party

yes goods can be transported directly to uttrakhand party however frieght will be either paid by you or delhi party as per mutual understanding if freight is paid by delhi party he will charge as you as reimbursement and if you pay frieght you will have to pay gst as reverse charge if applicable

now another provision is EWAY BILL govt has changed e way bill rules now transporter can also file e way bill on your behalf

you have to just tell the transporter (if you are paying freight ) about the invoice given by you to uttrakhand party and rest of eway bill will be issued by transporter