Once again, using my poor Japanese and Google, I translated this as (corrections welcome):

Yoshimitsu. Family name: Aoyanagi. Called Eigoro. His brother was Yoshihide.

First studied under Horie Okinari, called Mitsunari. (Note from Markus Sesko: who in turn was a student of Omori Teruhide, 1730-1798)

Later, became a student of Yoshikatsu. Signed Aoya(na)gi Yoshimitsu (kao)

Lions (shishi), bamboo and chrysanthemum, designs of fuchi-kashira are small ?

He lived in Edo, Kanda district, by the river. His Go (art name) was Ichiyodo. (note: Markus Sesko says Ichimudo)

According to Markus Sesko (The Japanese toso-kinko Schools) Yoshimitsu was a member of the Inagawa School in the Kanda district of Edo, founded by Naoshige (died 1739). He first studied under Horie Okinari, 1st generation master of the Horie School in Edo, born 1749. Yoshimitsu studied under the third generation master, Yoshikatsu (1725-1779) and was a member of the Aoyanagi family (Note: The samurai manor house of the Aoyagi/Aoyanagi family in Kakunodate, Akita is now a museum). It may be that Yoshimitsu was permitted to sign his work as he was a member of an important samurai family and so added his family name to the signature. The dates of Yoshimitsu or his contemporaries is not given in Sesko’s genealogy charts, but he was probably active around 1760-1820.

Both tsuba are signed Aoyagi Yoshimitsu with a kao (Markus Sesko reads the signature as Aoyanagi Yoshimitsu).

According to Japanese mythology the ho-o is a symbol of good luck and resides in paulownia trees. However, it said to only appear in times of peace, prosperity and, as it was a symbol of the Imperial house, some believed that it only appeared at the start of a new era. The leaves of the paulownia form the basis of the paulownia kamon (family crest) used by the Toyotomi clan and later by the Japanese Imperial family. I think that it is therefore possible that this daisho pair of tsuba was commissioned to coincide with the inauguration of a new Emperor and start of a new era. 1772 saw the start of the An’ei era (Emperor Hidehito), 1781 the start of the Tenmei era (Morohito) and 1818 the start of the the Bunsei era (Ayahito). There were also changes of the era in 1789 (Kansei), 1801 (Kyowa) and 1804 (Bunka) without a change in Emperor. Although there is no corroborative evidence, it seems probable that these tsuba were made to celebrate the assent of Emperor Morohito and the start of the Tenmei era in 1781, this being the date most likely to coincide with Yoshimitsu’s career.

Best regards John

(Just a guy making observations, asking questions, trying to learn)