I wonder if Liechtensteiner football clubs can compete in the UEFA Champions League?
Since Liechtenstein does not have a domestic league, they do not have a spot in the UEFA Champions League. Instead, the Liechtenstein Football Cup winner qualifies to the UEFA Europa Conference League.
If the Liechtensteiner team wins the UECL, they can compete in the UEFA Europa League in the next season. If the team won the UEL, then they advance to the UEFA Champions League in the next season.
- Edit (From @Don_Biglia's comment)
Currently, seven Lichtensteiner clubs are playing in the Swiss Football League system in various tiers, but they cannot qualify for any European competition through Swiss football league accomplishments. This is because Lichtenstein has their own domestic cup.
On the other hand, AS Monaco can qualify for the UCL through French Ligue 1 because Monaco does not have either domestic league nor cup competition.