No. iTel S41 does not have a hybrid sim slot. It has 1 dedicated slot for MicroSD card and 2 dedicated sim card slots.
Yes, iTel S41 does have the eye protection mode which reduces strain for long reading.
Yes, iTel S41 does have VoLTE support.
Yes, iTel S41 does have a memory card slot.
Yes, you can use 2 different WhatsApp accounts in iTel S41. Not only that, you can use 2 different Facebook, Instagram and Twitter accounts as well.