The assumption is that having the same file duplicated in different folders is normal. However, two copies of a file in the same folder is likely a mistake.
# in the folder containing all the SMDB files
for f in *.txt ; do
cut -f 1,2 "${f}" | \
sed -r 's|([A-Z].*)/.*|\1/|' | \
sort -d | \
uniq -d | \
while read l ; do
grep "${l}" "${f}"
echo
done
done | cut -f 1,2
0486aa0f4bfe649d168b050deb5452c0a6753e79a6902fa88dbc20e33fa85ab6 Atari 7800/4 Hacks/Mestor and Polax (Pac-Man Hack).a78
0486aa0f4bfe649d168b050deb5452c0a6753e79a6902fa88dbc20e33fa85ab6 Atari 7800/4 Hacks/Pac Pollux (PacManPlus).a78
3a3362940cc44777d373518a6a890fc84c3827fbc798545617826ce9bb7ab52d Atari 7800/4 Homebrew/Moon Cresta (USA) (PacManPlus).a78
3a3362940cc44777d373518a6a890fc84c3827fbc798545617826ce9bb7ab52d Atari 7800/4 Homebrew/Moon Cresta by Bob DeCrescenzo (V20111115).a78
3e7b989cdbb2b18d94408835dfc4d8467e5372dc940aad06d336720229088f76 Atari 7800/2 PAL EU A-Z/Sentinel (1991) (Atari) (PAL) [!].a78
3e7b989cdbb2b18d94408835dfc4d8467e5372dc940aad06d336720229088f76 Atari 7800/2 PAL EU A-Z/Sentinel (Europe).a78
3fe859be5c9728a27880977cf317f95c85d7221052aeb7f4ce18018e5ad55fd3 Atari 7800/4 Hacks/Pac-Man Collection (Sound Hack) (tep392).a78
3fe859be5c9728a27880977cf317f95c85d7221052aeb7f4ce18018e5ad55fd3 Atari 7800/4 Hacks/Pac_snd_hack by tep392 (Pac-Man Collection Hack).a78
48bceabcb1d3aaadd4469e78c1d4239f317eac7e41575d8705ffea484eaa18cb Atari 7800/4 Hacks/Xmas Time 2006 (jwierer).a78
48bceabcb1d3aaadd4469e78c1d4239f317eac7e41575d8705ffea484eaa18cb Atari 7800/4 Hacks/XmasTime (V20061225) (Beef Drop Hack).a78
8868ab99b3ee62ab64a0b2ad7d13ae412695637c2059dfb6a46a02ff5486f081 Atari 7800/4 Homebrew/Pac-Man 320 (Pokey) (PacManPlus).a78
8868ab99b3ee62ab64a0b2ad7d13ae412695637c2059dfb6a46a02ff5486f081 Atari 7800/4 Homebrew/Pac-Man Arcade by Bob DeCrescenzo (V20110810POKEY).a78
99507b4dff7f213b2dbe8e8ace65858353109cccaec4dec6070710a95c6fe197 Atari 7800/4 Hacks/Papa Smurf in Pacland (jwierer).a78
99507b4dff7f213b2dbe8e8ace65858353109cccaec4dec6070710a95c6fe197 Atari 7800/4 Hacks/Papasmurf in Pacland by Jeff Wierer (Ms. Pac-Man Hack).a78
a38b1a1e32724c83746ceb352f6cc0957e71a6bc5608235b34896f58ac83a945 Atari 7800/4 Homebrew/Pac-Man 320 (USA) (PacManPlus).a78
a38b1a1e32724c83746ceb352f6cc0957e71a6bc5608235b34896f58ac83a945 Atari 7800/4 Homebrew/Pac-Man Arcade by Bob DeCrescenzo (V20110810).a78
b599bafec9b38d3932c0ec3a82858f9cedb4b8437e4e2b35ad2eacccd31df98a Atari 7800/4 Hacks/Jr. Ms. Pac-Man (jwierer).a78
b599bafec9b38d3932c0ec3a82858f9cedb4b8437e4e2b35ad2eacccd31df98a Atari 7800/4 Hacks/Snow Day Jr. Pac-Man (jwierer).a78
bfe921ed28e1689b43c96f3df941336731865d57e9d3b6eccd5da688709183ac Atari 7800/4 Hacks/Jr. Ms. Pac-Man (Better Santa Hat) (jwierer).a78
bfe921ed28e1689b43c96f3df941336731865d57e9d3b6eccd5da688709183ac Atari 7800/4 Hacks/Snow Day (Jr. Pac-Man Hack).a78
bfe921ed28e1689b43c96f3df941336731865d57e9d3b6eccd5da688709183ac Atari 7800/4 Hacks/Snow Day Jr. Pac-Man (Better Santa Hat) (jwierer).a78
cbcc92c5f0e9845da83c8b5f6b6700044af5eeb98cb997aed9fa4059aa5b4395 Atari 7800/4 Hacks/Papa Smurf in Pacland II (jwierer).a78
cbcc92c5f0e9845da83c8b5f6b6700044af5eeb98cb997aed9fa4059aa5b4395 Atari 7800/4 Hacks/Papasmurf in Pacland II by Jeff Wierer (Ms. Pac-Man Hack).a78
The assumption is that having the same file duplicated in different folders is normal. However, two copies of a file in the same folder is likely a mistake.