What forms are required with an electronically filed Amended Return?

The electronic Form 1040, 1040-SR, and 1040-NR Amended Returns (with attached Form 1040-X) will require submission of ALL necessary forms and schedules as if it were the original submission, even though some forms may have no adjustments. The Form 1040-SS/PR Corrected returns will require submission of ALL necessary forms and schedules as if it were the original submission, even though some forms may have no adjustments. Note that Form 1040-X will not be attached to Form 1040-SS/PR.

https://www.irs.gov/filing/amended-return-frequently-asked-questions