I wouldn't transfer without checking on lining thickness and composition (needs to be tri-laminar). You can waste embryos if it isn't right for implantation. Some clinics don't do it to save cost but getting good embryos is hard and I personally wouldn't want to waste one. We also did ultrasound guided transfer which is a relief to see on the screen that it's being put back in the right place (though this is less important IMO as a very experienced FS can do this by feel)

All the best hope this cycle is successful for you! Try not to stress too much