Incorrect multi-index specific level sorting after an align
Hello,

Level sorting does not seem to work on the output of an align between two DataFrames when
- you align on multi-index
- you align on left dataframe
- left dataframe columns are lexsorted
- right dataframe contains an extra-level compares to the left one
- you're trying to sort according to that extra-level

Here is a sample code:

```python
import pandas as pd
import numpy as np

col1 = pd.DataFrame(
    [['a', 'g'],
     ['c', 'a'],
     ['b', 'w'],
     ], columns=['name', 'name2'])

col2 = pd.DataFrame(
    [
        ['a', 'g', 1],
        ['c', 'a', 5],
        ['b', 'w', 100],
        ['d', 'h', 3]
    ], columns=['name', 'name2', 'id'])

T = 100
data1 = np.random.randn(col1.shape[0], T)
data2 = np.random.randn(col2.shape[0], T)

col1 = pd.MultiIndex.from_frame(col1)
col2 = pd.MultiIndex.from_frame(col2)

df1 = pd.DataFrame(data1.T, columns=col1)
df2 = pd.DataFrame(data2.T, columns=col2)
df1_sorted = df1.sort_index(1)

# sorting works
df_a = df1.align(df2, 'left')[0].sort_index(1, 'id')
print(df_a.head())

# sorting does not work
df_b = df1_sorted.align(df2, 'left')[0].sort_index(1, 'id')
print(df_b.head())
```
Thanks for your help

**Output of ```pd.show_versions()```**

<details>
```
commit           : None
python           : 3.7.4.final.0
python-bits      : 64
OS               : Linux
OS-release       : 4.15.0-58-generic
machine          : x86_64
processor        : x86_64
byteorder        : little
LC_ALL           : en_GB.UTF-8
LANG             : en_GB.UTF-8
LOCALE           : en_GB.UTF-8
pandas           : 1.0.3
numpy            : 1.17.4
pytz             : 2019.3
dateutil         : 2.8.0
pip              : 20.1
setuptools       : 45.2.0
Cython           : 0.29.13
pytest           : 5.2.2
hypothesis       : None
sphinx           : None
blosc            : None
feather          : None
xlsxwriter       : None
lxml.etree       : None
html5lib         : None
pymysql          : None
psycopg2         : 2.8.4 (dt dec pq3 ext lo64)
jinja2           : 2.10.3
IPython          : 7.9.0
pandas_datareader: None
bs4              : None
bottleneck       : None
fastparquet      : None
gcsfs            : None
lxml.etree       : None
matplotlib       : 3.1.1
numexpr          : 2.7.0
odfpy            : None
openpyxl         : None
pandas_gbq       : None
pyarrow          : None
pytables         : None
pytest           : 5.2.2
pyxlsb           : None
s3fs             : 0.4.2
scipy            : 1.3.3
sqlalchemy       : 1.3.10
tables           : 3.6.1
tabulate         : 0.8.6
xarray           : 0.14.1
xlrd             : 1.2.0
xlwt             : None
xlsxwriter       : None
numba            : 0.46.0
```
</details>

