Is the Hebrew נראה a perfect verb or a participle? The MT pointing has it has a perfect verb (with a qamets under the aleph). However, the BHS footnote and the NET comments point out that the LXX translate it as if it were a participle (ὀφθήσεται which is a 3s future passive indicative). So the LXX doesn’t translate the form into a participle, but does encode into its morphology a future aspect which must be based on a reading of the MT as a participle.
The only difference between the two forms would be a seghol under the aleph (for the participle, נִרְאֶה) instead of a qamets (for the perfect, נִרְאָה).
The root of the verb is ראה. Niphal forms of III-He verbs can be found in BBH §25.4 (or in Van Pelts “Compact Guide” at p121).
The NET footnote is helpful in that it describes specifically the way in which each of those two forms would be functioning. A perfect would be taken as a prophetic perfect (as in IBHS §30.5.1e) and the participle would be a futurum instans (IBHS §37.6f).
Finally, the NET concludes that:
In either case, the point is that Moses was anticipating that the Lord would indeed appear to them on this day.
So the meaning and interpretation of the text is not really disputed, but it is a reminder that pointing is very significant and that the MT pointing is not necessarily inspired and needs to be examined carefully.