CREATE TABLE #Tab
(Var1 varchar(20),
val1  varchar(20),
var2  varchar(20),
val2 varchar(20),
var3  varchar(20),
val3  varchar(20),
var4  varchar(20),
val4  varchar(20),
var5  varchar(20),
val5  varchar(20))
INSERT INTO #Tab(Var1,val1,var2,val2,var3,val3,var4,val4,var5,val5)
VALUES ('Color','Red','Size',4,'Height','2inch',NULL,NULL,NULL,NULL),
('Color','Red','Size',5,'Height','2inch',NULL,NULL,'Length','1 cm'),
('Color','Red','Size',4,'Height','3inch',NULL,NULL,NULL,''),
('Color','Black','Size',6,'Height','1inch',NULL,NULL,NULL,NULL)


SELECT DISTINCT Cat,[Var] INTo #Var
FROm (SELECT Var1,var2,var3,var4,var5 FROM #Tab)t
UNPIVOT (Cat FOR [Var] IN (Var1,var2,var3,var4,var5))u 



SELECT DISTINCT Cat,Val INTO #Val
FROm (SELECT val1,val2,val3,val4,val5 FROM #Tab)t
UNPIVOT (Cat FOR Val IN (val1,val2,val3,val4,val5))u 


SELECT vr.Cat AS Var,
STUFF((SELECT ',' + vl.Cat FROM #Val vl WHERE REPLACE(vr.Var,'var','') = REPLACE(Val,'Val','') 
FOR XML PATH('')),1,1,'') AS Val
FROM #Var vr
ORDER BY Var
 
DROP TABLE #Var
DROP TABLE #val
DROP TABLE #tab

output
-----------------------------
Var	Val
-----------------------------
Color	Black,Red
Height	1inch,2inch,3inch
Length	,1 cm
Size	4,5,6