Nearly always in this chapter of Moroni, we have “I would exhort you” rather than simply “I exhort you”. One may wonder here in verse 8 if would was possibly lost early in the transmission of the text. In particular, we note for this example that Oliver Cowdery accidentally dropped the subject pronoun I as he copied the text from 𝓞 into 𝓟. It is possible that he actually dropped I would but inserted only the I when he corrected his copy. The level of ink flow for the supralinear I is slightly heavier, which suggests that he made this correction when he proofed 𝓟 against 𝓞. As noted under 2 Nephi 4:15, sometimes Oliver omitted the subject pronoun I, although usually momentarily. Quite clearly, the I belongs here in Moroni 10:8. The more difficult question is whether would should also be there.
Nearby verses in this chapter consistently read “I would exhort you” rather than “I exhort you”:
But then near the end of the chapter, we get variability:
And similarly, elsewhere in the text we get variability:
Thus there is no strong reason to emend Moroni 10:8 by adding would. The critical text will retain the corrected reading in 𝓟, “and again I exhort you”.
Summary: Maintain in Moroni 10:8 the corrected reading in 𝓟, “and again I exhort you”; there is no need here to emend the text in the verse by adding the modal verb would since elsewhere the text allows for variation in using would for this phrase.