How to get Photoshop to recognise Lacie drive in Scratch Disk options?? (Ventura 13.6)

Please help! Photoshop isn't working because the scratch disk is full, I have a lacie drive with 4.5TB available but it is not coming up as an option. Lacie is formatted as ExFAT, is this wrong? Searching the internet for answers, I've seen mention of photoshop needing permission granted to access external volumes via system preferences/security & privacy/ files and folders/ adobe photoshop "removable volumes". But Ventura doesn't seem to have this?? Is there another way to access it I can't find?

Other people say I have to reformat the Lacie in Disk Utility to Mac OS Extended (Journaled) but that this will wipe everything on the disk? I've spent days offloading every large file on to the Lacie I don't really want to have to bring it back again as the Mac was full, is there another way??

I've also cleared the cache in photoshop and deleted all unused applications, there is very little left on the imac except my photos which is huge (I'm an illustrator and use this for art files), but these should be in the cloud mostly as the Mac is set to off load to the cloud. Icloud is also huge but also shouldn't be present accept the most recent?

I'd be very grateful for any advice but I'm not very techie so simple terms would be fantastic!