There are two Options. Option-1 : Exporting individual Floor plans, Section Elevations etc.
Try these shown steps
Step 1 - Archicad Units setup
Step 2 - Exports DWG Translator Setup
Step 3 - Export DWG with required Translator
Step 4 - Start new file in AutoCAD with Imperial Units Template ( I am using web base App)
Step 5 - Use Xref to insert your Archicad DWG file
Check the inserted drawing for its unit length, it should be in Feet Inch and not only Inch
If willing to export Plan, Section, Elevations etc in single file then place them in "New Independent Worksheet" by using "copy - paste" and try to export that as DWG with same translator. Later open that file in AutoCAD, if default units are not Architectural then choose them from Units command. You wont loos the accuracy. For e.g. say 6 decimals will be considered as 6" and 240 decimals will be converted as 20'
But incase if you try to export the Layout with various drawings placed in it then that entire thing will be shown in AutoCAD Paper Space without units accuracy, in such case may be you have to cut paste the Paper space data to Model Space and later Scale it to make compatible for further needs,
Autocad default unit system (for Imperial/Architectural) is inches that means that if you type "6" it will presume that is 6" instead of 6'-0". The units from the exported file (from AC) will always show "Decimal" in Autocad unless you use add a "Template DWG" in the Translator (under "Save as") that already has the units set to Architectural.
For the section issue you will need to post a screenshot to see what is the problem. Take in consideration that Autocad "fills/hatches" do not have a "background pen" setting so they might become solid on the DWG. Also you can set up how to translate the fills in AC's translator setup.
For reference, Autocad has different limitations compared to AC which means that drawings will look different on export since Autocad cannot display them in the same way. Main issues as you have found are Units and Fills but that includes also Linetypes and Text. Creating a Template.DWG should minimize most of them.
eduardo rolón AIA NCARB Another of the forum moderators. Macbook Pro M1 Max 64GB ram OS X 10.XX latest AC25 US/INT -> AC08 Puerto Rico, BVI, Miami Vectorworks 2023