The information required to be in an attached statement is only being generated in a worksheet in the Lacerte 1040 and normally those are not included in an efiled return, how is Lacerte covering this requirement?
If you have auto-attach PDF turned on, Lacerte will attach a statement of aggregation to the return. If the auto-attach is not turned on, Lacerte will generate this e-file stopping diagnostic:
e-file: If two or more businesses are being aggregated for purpose of the Qualified Business Income (QBI) deduction, Schedule B - Aggregation of Business Operations must be attached to the efile. (ref. #51823)
In the upper right of Lacerte if you typed in the Search box 'Attach PDF' it will bring up this knowledge base article:
Attaching PDF Documents to an E-file Return
See the Note under the video. This tells you how to turn off auto-attach PDF, check to see if yours says yes to verify that it is turned on.
In order to have the Schedule B - Aggregation of Business Operations print with the client copy you would go to Settings>Options>Items to Print on the Left click on Client and on the right under Federal Worksheets check off Worksheets (general). Please note that this will print all the worksheets.