From Sierra to Big Sur on macbook pro 2017

Technically - Yes

Some may say the mid-step to High Sierra will better prepare the computer for the next upgrade to Big Sur. The upgrade to High Sierra would offer any Boot ROMs required to handle the drive conversion to APFS format that is included in the High Sierra for SSD drives.

If going that route to High Sierra first -  How to get old versions of macOS and verify what version this computer Qualifies to install.  For Best results use Safari to commence the download as Others may not work.

If going directly from Sierra to Big Sur >>

Tips How to Upgrade to Big Sur 

There are several points to consider before attempting the upgrade to Big Sur. The most important is Due Diligence on the part of the User and is a Prerequisite for a smooth upgrade.  

Point # 1 - Are there pre-existing Unresolved Software Issues. They should be resolved prior to upgrading - they may carryover to Big Sur making the system unstable / unusable.

Point # 2 - Are there any AntiVirus, Disk Cleaner, Optimizers, Un-installers, etc installed which should be removed as per Developers Instructions. They are useless, unneeded, cause havoc and interfere with the normal operation of the OS and may even Corrupt the OS requiring a Reinstallation. The Built-in Security of Big Sur is all that is required.

Point # 2 A - Commercial VPNs should only be used if Mandated by Corporate Head Office for working remotely. Otherwise - ones Privacy and Security touted by the VPN is suspect.

Point # 3 - What are the System Requirements ie: Empty Space Requirements specific to the Big Sur. Apple States Requiring 35.6 GB of Empty Space but suggest 50 GB

Point # 4 - Does the intended computer qualify for the upgrade.

Point # 5 - Are the installed Applications / Extensions compatible with Big Sur. Check with the Developer for compatible Apps / Extension or do they offer updates. Same goes for Third Party Drivers for Printer, Scanners etc.

Point # 6 - If upgrading from Mojave and earlier versions of macOS - Remember that Big Sur does not support anything 32 bit. These include Applications, Extensions and Drivers for any devices. There is no workaround.

Point # 6A - To check for 32 bit Applications - a good application to use is Go64 - safe to use.

Point # 7 - Do you have a Rescue Plan In-Place. This comprises having 3 Backups using 2 methods and 1 Off Site incase of Theft, Loss or Natural Disasters. A Time Machine Backup  is very useful and can be used to Revert to Previous Working macOS. For addition purposes - two Tested Bootable Clones each to separate external drives. This is insurance incase the upgrades goes sideways. At least one Tested Clone and / or Time Machine Backup should be Off - Site

Point # 8  - To upgrade to Big Sur will requires a quick, stable and reliable Internet Connection - preferred method is via Ethernet Connection. 

If not available and using Wifi - move computer as close to the Access Point / Router and disconnect all other devices connected to Wifi. Want the maximum bandwidth for the computer being upgraded to Big Sur.

I will defer to @ VikingOSX, but suspect this machine has the Touch ID / T2 chip.

By default - the T2 Chip is set to Not Allow Booting from External Drives even if the External Dive is a Clone.

To test the Clone will require the steps outlined in the follow link from Apple >>>>> About Startup Security Utility

MacOS uses the GUID partition scheme, not the Master Boot Record (MBR) partition scheme. Use a proper clone tool to copy your existing drive content to an external drive formatted as HFS+ Journaled (case-insensitive). One such clone tool is Carbon Copy Cloner which will allow you to clone your startup drive during the 30-day trial period, and if necessary, you can later boot from that clone too. Just copying files using Finder to an external drive may not retain proper permissions, nor bootable capability.

Verify that your current printer/scanner vendors support Big Sur with 64-bit drivers released after Nov 2020 as your current Sierra drivers will not work.

Cloning Software is required to perform this action. There are two I know of and not in any order.

SuperDuper and Carbon Cony Cloner.

The External Drive can not be formatted as Master Boot Record . It must in the same format as the Internal Drive of the computer being cloned.

I do know Carbon Copy Cloner does offer a 30 Day Trial but can not speak to SuperDuper

What specific Software was used to Clone the computer to external drive ?? Was the Destination Drive formatted correctly as mentioned by @ VikingOSX

This link from Carbon Copy Cloner on making a Legacy Bootable Clone especially as related to Big Sur

https://bombich.com/kb/ccc6/cloning-macos-system-volumes-apple-software-restore