I blogged last year about Mercury retrograde (in Gemini) trine Neptune retrograde (in Aquarius) as ‘talking through a fog’. Energy flows smoothly in a trine. Mercury (in Taurus) is currently making its third and final square to Neptune which is currently retrograding once again in Aquarius. The first pass was on 25 April, the second on 23 May, and the third on 9 June. Energy passing through a square can feel like it is forced over an obstacle or through a very narrow passage.
Mercury (albeit direct now) square Neptune can produce blocks in communication, perhaps resulting from fuzzy (Neptune) logic (Mercury), or overly idealistic (Neptune) thinking (Mercury). It may also drain (Neptune) the energy out of communication (Mercury), or too much thinking (also Mercury)! But I am not certain how many experience this — I’m certainly feeling it. It may be that my own natal Mercury is opposite my natal Neptune, or that Neptune is currently squaring the ruler of my Gemini Sun (Mercury) and conjunct the ruler of my chart (Jupiter).