Google translate has limited functionality in China. Download the Chinese translation module for offline translation. As you type it will offer you a translation--this happens offline. The arrow that finishes the job doesn't work, though, as it sends it off to Google's server.

Note that this does not work the other way around as the handwriting recognition engine isn't on the phone--you can't enter the Chinese at all without a connection.

The last time I was there I got a local sim, so long as I had a decent connection I had no problem with the VPN, but note that if your connection is marginal the VPN will be pretty close to unusable. This is also useful for using WiFi as almost all public WiFi requires you to enter your phone number and they respond with a text that either enables the connection or provides a password to use to log in. (Your username is your phone number.) This is the government trying to prevent anonymous internet use. (And note that internet cafes likewise do not permit anonymous use--you'll need your passport.)

I was using ExpressVPN on my last visit, it worked fine so long as the stuff involved wasn't too big. It would bog down into uselessness somewhere between 500k and 1mb. (And, of course, they released an update for my phone when I arrived. VPN off, blocked. VPN on, it would get stuck at about 4%. Practically every time I unlocked my phone it was nagging me about that update!)

Note that all the major cloud file hosts (dropbox etc.) are blocked over there also.

Language is mixed--the young educated people generally have enough English to communicate. The uneducated, though (the clerks, the taxi drivers etc) are another matter, their English is generally quite limited. Note that their written English might very well be better than their speaking--the most extreme case of this I encountered was a clerk in an internet cafe who as far as I could tell had zero English. Turns out she could spell all numbers perfectly but her pronunciation was so bad that even when I knew what she was saying it was hard to find the resemblance between what she said and English. Unless you're in a very tourist area I figure all communications with such people will be by gesture etc, or my phone. (Unless I'm alone I leave such matters to my wife, though--she's a native speaker.)

Note: Your hotel will almost certainly have business cards. Show them to the taxi driver. Some even have English/Chinese for "please take me to <hotel> <address>".

The situation is getting better--plenty of junior high/high school kids have at least some English, if I'm alone and standing still I'm often approached by groups that want to try their English out on me. (Strangely, schoolkids never approach us when we are together. The only time we have ever been approached was by a few graduate students and that was in a city with virtually zero foreigners--I didn't see a white face until we were leaving and some showed up for some sort of athletic competition.)

Note that lower end hotels (decent but nothing fancy) are likely not able to take foreigners, although some look the other way for foreigners accompanied by locals--they register the room to the local's ID (Even if the foreigners and locals are in different rooms) and ignore the registration requirements. (The government insists on knowing where every foreigner spends the night. The hotel does this registration for you, if you're staying in a private place you need to go down to the police station yourself within 24 hours. Requirements vary, supposedly you need the owner with you but we have done it entirely on our own in some places.)

Since this is a business trip, beware of industrial espionage. Don't bring any sensitive data you don't have to. The most security-conscious have separate devices used only for China.