You can put them in if you can be sure that they are suspended in the water. The bulbs of the ph, orp and salinity can't touch rocks or the sand. The temp probe is more forgiving.
Make sure that you calibrate all of the probes before you use them.
Long term you are best keeping the cable out of the water - keep the probe 90% submerged but the top and cable out. This is because the flexible coating on the cable will harden over time with exposure to SW. You’ll get a longer life out of the probes if you can keep it out.