$ git clone -q https://github.com/karlforshaw/opengamedb.git
$ cd opengamedb/
$ cut -d, -f1 names.csv |xargs -i% cat %.csv|cut -d, -f1|sort|uniq|sed 's/^"//'|sed 's/"$//'|grep -E '^(.*)\1+$'|uniq
[snip]
***
1010
101010
222
999
Ape QuestApe Quest
BeatBeat
DingDingDing
GUNGUNGUN
JUJU
KARAKARA
MochiMochi
MokMok
niconico
OlliOlli
QbQbQb
ROCKETSROCKETSROCKETS
ROWROW
RRRR
RUNRUNRUN
TripTrip
VVVVV
VVVVVV
YamaYama
zzzzz
$

There do appear to be games like that (though “Ape QuestApe Quest” appears to be a typo).