Aloe vera prefers indirect sunlight, even light shade, as too much light burns its leaves. Cacti need direct light, so it's best paired with other sun-loving plants.
Sedum needs thorough watering when first planted to get established in the soil, and then it needs watering when the first 2 inches of its topsoil are dry.
On the other hand, echeveria only needs a drink once all of its soil has dried. Subjecting it to the watering needs of sedum may cause it to suffer root rot and attract mealybugs.
Ceropegia woodii's heart-shaped leaves can burn easily in the sun, so it’s best kept in bright yet indirect light. However, cacti prefer bounties of direct lighting.
Aeoniums need watering when the first inch of topsoil is dry, but this method would waterlog sempervivums since they need a refill when all the soil is dry.
Additionally, sempervivums can tolerate colder climates — as low as 0 degrees Fahrenheit — while aeoniums need at least 65 degrees Fahrenheit for the best growing conditions.
Lithops is winter dormant, whereas othonna is summer dormant, making these plants incompatible. You should avoid watering othonna when it's resting during summer.
However, lithops will be in the middle of their growing season and need the hydration. Therefore, it won't be possible to satisfy both their care needs when rooted together.