In my opinion, dwarf gouramis (Trichogaster lalius) are nothing but trouble and the sooner the governments around the world ban them from coming into the country the better. They have been inbred for years and are so screwed up from diseases, they are just not worth keeping. If you want one or a pr then by all means get one, but keep them in their own tank so they don't bring any diseases into the main tank.
The males are colourful and the females are silver/ grey.
If you can find locally bred dwarf gouramis then they are a different kettle of fish and usually do very well. However, 99.9% of dwarf gouramis are bred in the same contaminated ponds in Asia and that is where they contract the diseases that kill them and most other fish.
When they are in their own tank, feed them and do water changes/ gravel cleans after you have fed & cleaned your other fish tanks. And use a separate gravel cleaner and bucket for the gourami tank. Basically treat them as diseased and leave them in a species only tank.
If you do get some and keep them in their own tank, after they die and before you add any new fish to that tank, you should disinfect everything with bleach or boiling water.
If they don't have Tuberculosis (TB) or the Iridovirus, or any other diseases, they make a colourful display and do well. But everyone I have seen over the last 30 years has bloated up and died well before its time.
There are a number of other small labyrinths (gouramis & Bettas) that do well. Sparkling gouramis, Honey dwarf gouramis, Betta imbellis or Betta pugnax do well in peaceful community tanks. However, B. pugnax grows to about 4 inches and will eat small fish like neon tetras, so they should be housed with peaceful fish that don't fit in their mouth.