I'm not sure when you want this to occur to help you with the launch point, but you can do this from an automation script. Go from your child object to the owner and then get the set that you're interested in. For example:
owner=mbo.getOwner()
matrecSet=owner.getMboSet("PARENTMATRECTRANS")
Records can be added to the beginning of the set, at the end of the set, or at a specific point defined inside the set depending on the method called. Testing receiving (both selecting ordered items and users utilizing new row manually) it seems to add at the end. So to get the last MBO in the set, you can call something like this:
matrecMbo=matrecSet.getMbo(matrecSet.getSize()-1)
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Steven Shull
Director of Development
Projetech Inc
Cincinnati OH
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Original Message:
Sent: Mon April 19, 2021 04:59 AM
From: Blaz Rakar
Subject: Automation script get current mbo values from UI
Hello,
I have a question for my case:

Is possible to get value from child MBO table MATRECTRANS from column "Številka prejema" last added value which is not saved in database at the moment?
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Blaz Rakar
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#AssetandFacilitiesManagement
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