Hi Sasi, from the internal case I did some testing with PS R12.7
I cheated a bit, I did xpsexport, then viewed using SMPolicyReader to build my xcart, then tried xpsexport with the xcart.
Siteminder Policy Reader
Using SMPolicyReader to generate xcart selection.
But I tried this :
1) OpenID Provider
(note my first version of this post has this as failed - it was user error however, as I must have been using older backup, and the xid had changed - using the correct xid then the export worked fine - Mark 7-Feb-2019)
This did not seem to export : I could grab the id :

RIght click add to XCart then Tools/XCart gives a screen then save : gives :
# Type: CA.SM::OAuthIdP
# (I): Name : "null"
# (C): Desc : "OAuthIdP@21-2daea3f1-02bf-49a5-8cde-13809ec34ec8"
CA.SM::OAuthIdP@21-2daea3f1-02bf-49a5-8cde-13809ec34ec8
And then run the export :
> xpsexport output2.xml -xf testxcart.txt -npass
Then it all worked fine :

2) OpenID Client
This did seem to work.
I selected the OIDCClient :
Then with the xcart, it can show refetences, it had one OIDCAdminConfig : so I added that to the cart as well:

Saving the xcart gives :
# Type: CA.FED::OIDCClient
# (I): Name : "www-demo-com"
# (C): Desc : "CA.FED::OIDCClient@049a2973-ea10-4fc0-877a-d44b3e6e0725"
CA.FED::OIDCClient@049a2973-ea10-4fc0-877a-d44b3e6e0725
# Type: CA.FED::OIDCAdminConfig
# (I): Name : "openId-provider-example"
# (C): Desc : "CA.FED::OIDCAdminConfig@87b4d212-b07e-4b40-bfb8-5da126ebda9c"
CA.FED::OIDCAdminConfig@87b4d212-b07e-4b40-bfb8-5da126ebda9c
Then I ran the export - and it did export items:
>xpsexport output.xml -xf testxcart2.txt -npass
That did export those two items, and variety of other items certs etc as well.

That is header of output (I have some XTrace items set so it prints long list of stuff).
I did check and you can get to those items via XPSExplorer as well to build xcart as normal.
And it gives same result from xpsexport once built up xcart list.
Cheers - Mark