19 inch S5 wheels on 2020 S7

[ceri]

Hi, had 2018 A7 50 which had 19 inch wheels that bought new winter tyres last year, since sold the A7 and bought S7 with 21 inch wheels, priced winter tyres for it and £325 a wheel. Needed winters for trip to Alps next week so bought refurbed 19 inch wheels and put winters on, cost £800 all in. Seemed good fix to avoid higher cost of new 21 inch winters and thought handy to have option to swap wheels in bad weather and back myself. Was told wheels would fit and be right offset etc and swapped them over yesterday. All feels/runs right but tyre sensors not working. Looks like it's a special valve in tyre that isn't on new ones. Not big issue as would be swapping wheels back when come back. Only concern is, is there an issue that not considered. Ignore looks as they look OK its more if not considered a left field issue or one staring ne in face but can't see it! TIA