When you can’t apply Juki’s answer then after selecting the desired version of media you can use Fiddler to determine where the files are located.
SQL Server 2019 Express Edition (English):
- Basic (~249 MB): https://download.microsoft.com/download/7/c/1/7c14e92e-bdcb-4f89-b7cf-93543e7112d1/SQLEXPR_x64_ENU.exe
- Advanced (~790 MB): https://download.microsoft.com/download/7/c/1/7c14e92e-bdcb-4f89-b7cf-93543e7112d1/SQLEXPRADV_x64_ENU.exe
- LocalDB (~53 MB): https://download.microsoft.com/download/7/c/1/7c14e92e-bdcb-4f89-b7cf-93543e7112d1/SqlLocalDB.msi
SQL Server 2017 Express Edition (English):
- Core (~275 MB): https://download.microsoft.com/download/E/F/2/EF23C21D-7860-4F05-88CE-39AA114B014B/SQLEXPR_x64_ENU.exe
- Advanced (~710 MB): https://download.microsoft.com/download/E/F/2/EF23C21D-7860-4F05-88CE-39AA114B014B/SQLEXPRADV_x64_ENU.exe
- LocalDB (~45 MB): https://download.microsoft.com/download/E/F/2/EF23C21D-7860-4F05-88CE-39AA114B014B/SqlLocalDB.msi
SQL Server 2016 with SP2 Express Edition (English):
- Core (~437 MB): https://download.microsoft.com/download/4/1/A/41AD6EDE-9794-44E3-B3D5-A1AF62CD7A6F/sql16_sp2_dlc/en-us/SQLEXPR_x64_ENU.exe
- Advanced (~1445 MB): https://download.microsoft.com/download/4/1/A/41AD6EDE-9794-44E3-B3D5-A1AF62CD7A6F/sql16_sp2_dlc/en-us/SQLEXPRADV_x64_ENU.exe
- LocalDB (~45 MB): https://download.microsoft.com/download/4/1/A/41AD6EDE-9794-44E3-B3D5-A1AF62CD7A6F/sql16_sp2_dlc/en-us/SqlLocalDB.msi
SQL Server 2016 with SP1 Express Edition (English):
- Core (~411 MB): https://download.microsoft.com/download/9/0/7/907AD35F-9F9C-43A5-9789-52470555DB90/ENU/SQLEXPR_x64_ENU.exe
- Advanced (~1255 MB): https://download.microsoft.com/download/9/0/7/907AD35F-9F9C-43A5-9789-52470555DB90/ENU/SQLEXPRADV_x64_ENU.exe
- LocalDB (~45 MB): https://download.microsoft.com/download/9/0/7/907AD35F-9F9C-43A5-9789-52470555DB90/ENU/SqlLocalDB.msi
And here is how to use Fiddler.