Newbie Questions (Projector, AppleTV, and Delays)

For your Sony projector you can use the SonyADCP integration: Community Integration - Sony Projectors (ADCP for newer models)
You should always prefer to use integrations as they are ip based. IR should only be used if there are no other options like Bluetooth. IP is also bi directional so you get feedback if your command failed and additional informations like media playback infos with cover art and the current playback position.