One attr key script

string $myObjects [] = ` ls -sl`;

string $myAttr [] = ` channelBox -q -sma mainChannelBox`;
 
for ($myNode in $myObjects) {
    for ($myNodeAttr in $myAttr) {
        setKeyframe ( $myNode+"."+$myNodeAttr );
    }}

Simply select an attribute and run the script. It will key only the selected one.