Technology is a universal language so training DBAs from other countries is not really a challenge when covering technical aspects. But here are a few things to keep in mind.
Time zones- lunch breaks are different for different people.
Office hours – Availability of daylight usually impacts office hours and typically there is a difference between winters and summers.
Cultural sensitivity – while technical trainings usually don’t have a lot of off topic discussions it’s important to use the right examples or analogies
Hands on – when doing trainings online it makes sense to test the lab setup from the participants point of view since they are located elsewhere and network connectivity and the availability of toll free numbers play a crucial role
Make it interactive – Classroom trainings have the advantage of keeping the participants in the room so there is more opportunities to bring back attention if a few people drift off. In online trainings its important to make sure nobody drifts off in the first place.
Share your webcam – Seeing the trainer allows participant to connect better and relate with the trainer, additionally the best trainers usually use a lot of hand movements which are lost when webcam is not shared
Stick to timings- structure is important since it’s easy to lose track of time and convert the training into a meeting without knowing it
These are just a few basic things I noticed over time and probably could be useful for others too.