/linkshell or /l = current equipped linkshell
/linkshell1 or /l1 = #1 linkshell
/linkshell2 or /l2 = #2 linkshell
and so on...

Also, using /linkshell1-8 or /l1-8 would only chat in that specific linkshell not switch the actual linkshell
to actually switch default linkshell use /chatmode linkshell1-8 or /cm l1-8 for short

Can we have that plz SE?