Can anyone share "Edit link" action on Custom related list?

Hi,

I think you have created VF page where you are showing list on some condition via apex and clicking edit link you want to open detail page in edit mode. For that you have to create PageReference type method in which you have to pass the record Id(getter setter variable).

try this -

PageReference acctPage = new PageReference('/'+{!recordId}+'/e?retURL=%2Fa'+ID);

Hope this helps.