Polish statesman one risks unsettling, crossing floor (8)
I believe the answer is:
sikorski
'polish statesman' is the definition.
(I've seen this before)
'one risks unsettling crossing floor' is the wordplay.
'one' becomes 'I' (Roman numeral).
'unsettling' indicates an anagram.
'crossing' indicates putting letters inside.
'floor' becomes 'ko' (I've seen this in other clues).
'i'+'risks'='irisks'
'irisks' is an anagram of 'sirski'.
'sirski' going around 'ko' is 'SIKORSKI'.
(Other definitions for sikorski that I've seen before include "Polish PM" , "Polish statesman" .)