OnePlus 8 Pro (in the gel case that it came with)
Antenna Location: Between volume up/down buttons and the 1+ Logo on the back.
Best orientation (xFD): Parallel or Perpendicular to the side
NeXT in L0: NFC Tools Pro - Read [OK]; Write Record 0 [OK]
xSLX in R0: NFC Tools Pro - Read [OK]
Spark 2 (wrist area): NFC Tools Pro - Read [OK] ; Vivokey App - Read [OK]