Don't think so, the game might be using 16bit samples. What i don't understand is why they didn't add other 16bit cards as options, instead locking it out to only SB16.

So probably it would be necessary to create a configuration program to choose other 16-bit sound cards, which would then modify some game file.

Concerning 8-bit cards, what about games which use 8-bit and 16-bit cards? Do they use 8-bit and 16-bit samples, or do they use 8-bit samples for both cards, or do they use 16-bit samples for both cards (with some trick on 8-bit cards)?

According to Moby Games it supports Sound Blaster 16 and Sound Blaster Pro but I see lots of mentions of audio trouble with people running the GOG version. Review pages mention "Sound Blaster 16 or 100% 16-bit compatible.

On DOSBox.com I saw a snippet of the config file:

[DIGITAL]
DeviceName = Sound Blaster 16/AWE32
DeviceIRQ = 5
DeviceDMA = 5
DevicePort = 0x220
DeviceID = 0xe018
DeviceMonoID = 0xe017
Stereo = 0
TimerRate = 60
Flip = 0

It might be using HMI audio drivers as they have a similar config. You might get away with changing the config manually and/or add HMI driver files. It's a long shot though and I have no idea what happens if a Sound Blaster Pro gets offered 16-bit files.

It's strange. My original version of the game doesn't use any config file. It uses only one EXE file and four big HPF files.

That config file belongs to another game, my bad. I landed on that page through a search engine, assuming it was the correct title. When I check the manual I see this:

"Some sound cards may be advertised as being 100% Sound Blastercompatible but still may not work with The Last Express. This is because many 16-bit sound cards only emulate 8-bit Sound Blaster cards. The LastExpress requires a 100% Sound Blaster 16 compatible card."

That with the absence of a config file and the DOS version seemingly having no setup... I don't think it's possible. Perhaps you can try to extract the HPF files to see if there is anything else to try.

Art wrote on 2021-02-16, 19:42:

Concerning 8-bit cards, what about games which use 8-bit and 16-bit cards? Do they use 8-bit and 16-bit samples, or do they use 8-bit samples for both cards, or do they use 16-bit samples for both cards (with some trick on 8-bit cards)?

There are games that use 8 bit samples on 16 bit cards, such as Duke3D. I'm not sure if it always mixes in 16 bits internally, but with 16 bit cards it will output a 16 bit mix.
See A List of DOS Games with 16-Bit Sound, although that thread doesn't mention the Last Express.
I don't have first-hand experience with a game that comes with 16 bit samples yet supports, and plays them on, 8 bit cards, but I don't doubt those exist; again, the game might be mixing with 16 bit resolution internally.