Hey there...it's me
again,
I have checked in the connection Vault in Advance Steel 2018 for a beam to beam complete joint penetration connection and it does not seem to exist.
Granted in Advance Steel you are able to add manual elements and bricks from the Custom connections category in the Advance Steel Tool Palette.
You can create you own specialized connection where you can save and use it from project to project and thats great to be able to implement other features, elements and objects in an already existing custom connection.
I was able to use the End plate from the Connection Vault for the end of the W10x100 and to attach the W8x28 to the end plate by a shear plate, I used the "Plate along beam web" brick tool.
I used the bolts tool and used the "Rectangular 2, points" tool to place and locate the bolts on the plate and beam and thats great.. but it would be nice if this connection was implemented into the Connection Vault, Platform Beams category.
.....Juss sayin.
Please see attachment at my attempt to make a custom connection. 
Attached is also the PDF
Best regards,
Janet
Graitec CANADA