Export the source source alignment and profiles out to xml.
In the Prospector Tab of the Toolspace, select the source alignment and choose "Export LandXML..."
Tick the profiles you want to transfer, and click ok.
Save the XML file.
Do the same for the Destination Alignment, and save it with a different name.
Open both XML files in notepad.
From the XML that has your source Alignment details, copy the section from "<Profile name=" (source alignment name) down to "</Profile>"
Paste the above into the XML that contains your Destination Alignment information in it, below the "</CoordGeom>" section and before the "</Alignment>" assuming the destination alignment has no profiles or sections. You will have to change the source alignment name in the "<Profile name=" section to match the destination alignment.
Then save the xml. Back to civil 3d select "LandXML" from the "Import" panel on the "Insert" tab. Select the destination XML you just modified.
If it is all good, you should see the panaroma pop up with a message saying LandXML import conflict: Updating <Alignment> <Alignment - (1)> where <Alignment - (1)> will be your destination alignment name.
Go to the prospector tab on the toolspace and expand you destination alignment and you should see the newe profile there.
If a post provides a fix for your issue, click on "Accept as Solution" to help other users find solutions to problems they might have that are similar to yours.
Andrew Puller
Maitland, NSW, Australia
Windows 11
Intel core i7 11800 @ 2.30 GHz with 32GB Ram
Civil 3d 2023