I had the same problem, on the same model.
Potential resolution: I deleted every 32-bit app on the iPad. The problem has not appeared since.
Method: I went through all my apps and deleted any that either needed to be updated, or that crashed.
Logistics: With 400+ apps, it took a couple of hours. I made life easier by avoiding apps which I had used fairly recently. I had a list of 32-bit apps (from iOS 11 – apparently not available in iOS 13), which helped me to double-check that I had got them all.
Background: I was able to access the logs via iMazing – the logs I was interested in were called "Preferences-yyyy-mm-dd-hhmmss.ips". In each, the crashing thread was named "Dispatch queue: com.apple.preferences.spotlightIndexQueue". The fault in this thread, each time, was "esr: 0x56000080 Address size fault". This is similar to the problem as described by @TheOriginalZamfield.
I wondered if preferences was trying to build its list of apps, expecting 64-bit apps and failing to deal with one (some, or all) 32-bit app(s). Apple support hinted at a confirmation, saying that this was a known problem, and they would escalate to a more-senior tech if it persisted after updating all apps.
The following had no apparrent immediate effect: Restart. Hard reset. Update while in "recovery mode". Deleting a few 32-bit apps.
I removed the following 32-bit apps (list may be incomplete):
3DSun
AC-7 Pro
AccuWeather
AdobeIdeas
Always Up
Aweditorium
Bookbag
ClockPro
CrashDrive
Cut the rope (candy cane icon)
Cut the rope (round candy icon)
DJSpooky
DPControl
DismountLite
Drainworks
Ellatron
Eurosport
Eyewitness
FatboySlim
Firmament
FlockControl
Genesis
GoodReader
Guardian
H4NG
Inkpad
Jasuto
Jenga HD
Jot! Free
JotBookFree
Labyrinth LE
Livenotes lite
MagnetMeter
MongoliadHD
NightStand
PianoAngelFree
PlaneFinderHD
Player (Eurosport)
Prezi
PulseNews
RCPhysics
Ragdoll2 Lite
Rolando Lite
SPectroWalls Lite
ShapeWriter
Shazam (old)
SketchBook
Storybook
TODoist (crashes)
TVGuide@UK
TestStudio
The Economist (old)
TouchPhysics
Trainyard
VolVox
Volvox
WeeMee
Wikihood
djay
eBanner
iDrum
last.fm
myLite
(Piano - iOS 13 compatible, but crashes)
(iHandyLevel - iOS 13 compatible, but crashes)