Windows certutil exports with empty password but openssl pkcs12 fails

Question

Here are the commands I follow to create a certificate and accept it usin Windows Server's CA Server.

certreq -new -f -q $answerFile.FullName $requestFile.FullName
certreq -submit -f -q -config $AuthorityCertificatesServer $requestFile.FullName $publicCertFile.FullName | Select-String 'Id. de solicitud: (\d+)' | ForEach-Object { $_.Matches.Groups[1].Value }
certutil -resubmit $ID_SOLICITUD
certreq -retrieve -f -q -config $AuthorityCertificatesServer $ID_SOLICITUD $publicCertFile.FullName
certreq -accept -f -q -user -config $AuthorityCertificatesServer $publicCertFile.FullName

certutil -f -user -exportPFX -p '' My $thumbprint $pfxCertFile.FullName NoRoot

openssl pkcs12 -in $pfxCertFile.FullName -clcerts -nokeys -out $DOMAIN.crt -passout pass: -passin pass:
openssl pkcs12 -in $pfxCertFile.FullName -nocerts -out $DOMAIN.key  -passout pass: -passin pass:

I have problems with the last 3.

certutil -f -user -exportPFX -p '' My $thumbprint $pfxCertFile.FullName NoRoot

This creates the pfx file (I assume with an empty password)

But these 2:

openssl pkcs12 -in $pfxCertFile.FullName -clcerts -nokeys -out $DOMAIN.crt -passout pass: -passin pass:
openssl pkcs12 -in $pfxCertFile.FullName -nocerts -out $DOMAIN.key  -passout pass: -passin pass:

Fail with

Mac verify error: invalid password?
New-WebHostingCertificate : Couldn't convert from PFX to Apache CRT/KEY
En línea: 1 Carácter: 1
+ New-WebHostingCertificate mywebsite.com
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [Write-Error], WriteErrorException
    + FullyQualifiedErrorId : Microsoft.PowerShell.Commands.WriteErrorException,New-WebHostingCertificate

Mac verify error: invalid password?

Any idea why?