Setting flags to show three buttons
You could take an object and check if the action exists. If so, take the value as key for assignment.

const actions = {
        accept: 'showAcceptButton',
        reject: 'showRejectButton',
        transfer: 'showTransferButton'
    };

for (const element of actionsReferences) {
    if (element in actions) {
        this[actions[element]] = true;
    }
}