Teams LSU played twice in a season:
1900 Milsaps
1904 Louisiana Tech
1943 Georgia
1943 Texas A&M
1959 Ole Miss
1997 Notre Dame
2001 Tennesssee
2003 Georgia

That is all the ones I could find real quick.

In 1943 there were not many teams playing football due to the war that is why you see LSU play both Georgia and Texas A&M twice.