"act as a proxy" is correct and usable in written English.
You can use it to describe someone who is taking the place of another person in a situation, such as a voting or purchasing decision. For example: "In the absence of the CEO, the CFO was invited to act as a proxy at the shareholders meeting."
She will likely announce her candidate, who will act as a proxy, later this month.
"These companies act as a proxy between the organisation's web servers and the general Internet," says Reynolds.
Htin Kyaw, a close adviser, was elected president this month and is expected to act as a proxy for Aung San Suu Kyi.
He is expected to act as a proxy to Aung San Suu Kyi, who has not commented in detail on how she plans to run the country.
It is easy, costs nothing, can act as a proxy for having to think deeply about any issue and makes us feel superior in several ways.
The MHC is also thought to act as a proxy for general outbreeding, with all the hybrid vigour that can bring.
But there's arguably a sense in which a trip around the world can act as a proxy form of relationship therapy, catalysing the negative dynamics of a relationship into resolution.
Before Aung San Suu Kyi won a victory in the November elections, she promised to be "above the president" – Htin Kyaw is a trusted school friend who is expected to act as a proxy.
Chinese hardliners see these moves as Japan's willingness to act as a proxy of the US in its efforts to contain China's rise and expand US presence and influence in the Asia-Pacific region.
Suu Kyi, who is barred from the presidency under an army-drafted constitution, has made clear she will be "above the president" and Htin Kyaw is expected to act as a proxy.
FBI background checks, which act as a proxy for gun sales, hit a record 23.1m in 2015 – more than two-and-half times as many as those processed a decade ago.
