You can code it yourself by using a python script inside dynamo.
Here are some topics that solved this problem.
Creation of load in contour(message 14)
https://forums.autodesk.com/t5/robot-structural-analysis-forum/api-macro-for-updating-panel-contour-loads-from-excel/td-p/4756971
Creation of the panel by python script
https://forums.autodesk.com/t5/robot-structural-analysis-forum/creation-of-panels-in-rsa-with-rsa-api-via-dynamo/td-p/8844346
Message from Aug 5 calculate model
https://forum.dynamobim.com/t/structural-analysis-for-dynamo-panel-surface-loads/34046
Be aware that when you use a python script for the loads, the build in node doesn’t work anymore.
@Maciek_Kubica Is it correct that bars and panels/claddings are listed in “the same ID numbers”?
I mean when i create a bar with a python script with number 1, and try to create a cladding also with number 1 i get an error. if i change the cladding to a number that is not in use by bars it works.
If you have more question regarding the code for planar loads let me know.
gr Edward