As many other posts i've read, I am trying to override the standard "New" button in a related list with a lightning component so that we can auto populate some fields for a client. I want to be able to keep the functionality of choosing a record type and displaying the associated page layout for that record type in a "Create new record" modal.(User profiles are irrelevant in this matter) I was looking at the standard salesforce code through the web dev console and was wondering how salesforce determines what page layout to render and if it is possible to manipulate this in a lightning component to pre-populate fields.
Otherwise what would be the best approach to auto-populate fields while dynamically using page layouts
I have been following this example but would like it to appear in a modal, same as standard functionality https://sfcure.com/2018/09/15/rendering-lightningrecordeditform-based-on-the-page-layout/