I submitted a recent game for computer analysis with the first four moves as follows:
1. f4 d5
2. Nf3 Nf6
3. d4 c5
4. e3 Bg4
The suggested alternative to 4. ….. Bg4 was 4 ….. Nc6
Later I submitted a second game for computer analysis with the same initial moves (but in a different sequence), and the suggested alternative to 4. ….. Bg4 was 4. ….. cxd4
Thus, the computer analysis seems to be inconsistent, treating identical positions differently. Comments are awaited!