user23690: [FEN "r2q1rk1/1p3ppp/p4n2/2Pp4/1Pn5/P1Bp3P/3N2P1/R2QN2K b - - 4 21"]

With Black to move Ne4 is not even in top 5 moves and engine says its an inaccuracy. I know it considers fastest winning moves and positional moves too but Ne4 should be a move not an inaccuracy. Ne4 is also a forcing move with many threats.

user12629: Calling it an "inaccuracy" is nothing more than the engine saying that it evaluates the position after one move to be a certain amount better than after another move. It doesn't necessarily mean a move is "bad".
Both d-pawns cannot be kept no matter what Black does. After 1...Ne4, if White plays Nxe4, the recapture will leave the c4 knight without a defender, and it doesn't have a lot of places to go. White can win the pawn on e4 and attack that knight. And the dark squares around the Black king are just a bit weak. Black is still winning though.
If instead Black plays ...d4, this forces some trades. Simplifying the position seems like a good idea for Black, since they are winning. Overall Stockfish likes this option better.
Here's a comparison showing what the next few moves might look like for each option:
[FEN "r2q1rk1/1p3ppp/p4n2/2Pp4/1Pn5/P1Bp3P/3N2P1/R2QN2K b - - 4 21"]

1...Ne4 (1...d4 2.Nxc4 dxc3 3.Qxd3 Qxd3 4.Nxd3 ) 2.Nxe4 dxe4 3.Qg4 g6 4.Qxe4 * 


23690: <pre><code>[FEN &quot;r2q1rk1/1p3ppp/p4n2/2Pp4/1Pn5/P1Bp3P/3N2P1/R2QN2K b - - 4 21&quot;]
</code></pre>
<p>With Black to move Ne4 is not even in top 5 moves and engine says its an inaccuracy. I know it considers fastest winning moves and positional moves too but Ne4 should be a move not an inaccuracy. Ne4 is also a forcing move with many threats.</p>
 12629: <p>Calling it an &quot;inaccuracy&quot; is nothing more than the engine saying that it evaluates the position after one move to be a certain amount better than after another move. It doesn't necessarily mean a move is &quot;bad&quot;.</p>
<p>Both d-pawns cannot be kept no matter what Black does. After 1...Ne4, if White plays Nxe4, the recapture will leave the c4 knight without a defender, and it doesn't have a lot of places to go. White can win the pawn on e4 and attack that knight. And the dark squares around the Black king are just a bit weak. Black is still winning though.</p>
<p>If instead Black plays ...d4, this forces some trades. Simplifying the position seems like a good idea for Black, since they are winning. Overall Stockfish likes this option better.</p>
<p>Here's a comparison showing what the next few moves might look like for each option:</p>
<pre><code>[FEN &quot;r2q1rk1/1p3ppp/p4n2/2Pp4/1Pn5/P1Bp3P/3N2P1/R2QN2K b - - 4 21&quot;]

1...Ne4 (1...d4 2.Nxc4 dxc3 3.Qxd3 Qxd3 4.Nxd3 ) 2.Nxe4 dxe4 3.Qg4 g6 4.Qxe4 * 
</code></pre>
