Is it possible to use both Loop FX at the same time?
Yes, it is.
Either switch the FX toggle to the secondary Loop FX (setting of the first is kept) or use a double click after the primary Loop FX has been activated to add the second FX on top. The FX switch Led will mirror the FX status: green = reverse FX, red = 1/2 speed FX, green + red = both FX are active. Double click again to deactivate the secondary FX.