You can represent the decomposition using Requirements, Requirement Group and Requirement Group pairing.
For example, regarding the design shown above, there is a possibility of malfunction that could occur from wrong transmission of the “Send Position” request or its loss signal. So we can design the SM-001 (Safety Mechanism 001) that we implement dual detection systems and add priority judgement as below:
Create a “Intended Function” Requirement Group and associate it with “FR-100” Requirement with Constraint-pairing.
Also, create another Requirement Group and let it associated with newly added “FSR-001” and “FSR-002” requirements that are included in the new SM-001.
You can decompose by pairing these two Requirement Groups with “Requirement Group Pairing”.
This is how decomposition works.
After decomposing, you can still change the Requirement’s ASIL and names.