TL;DR: Skip the pricey Canon stuff and grab a Godox... cheaper and honestly more reliable in my experience. Oh man, I totally get it... Canon prices are literally insane. I used to be a brand purist but unfortunately, my expensive Canon flashes kept failing on me after a few years of heavy use. I mean, it was SO disappointing for the price. For your 80D and 90D setup, I highkey suggest looking at the Godox V860III-C TTL Li-Ion Flash for Canon. It's around $230 and the lithium battery is a lifesaver. If that's still too much, basically everyone I know uses the Godox TT685II-C TTL Flash for Canon which is like $130. I had issues with Yongnuo units overheating during event shoots so I wouldn't go that route. Godox is just more reliable for dual-body setups cuz the trigger system is built-in. Anyway, save your money... peace! 👍

Seconding that! Dont skip the Godox V860III-C Speedlite for Canon. Its Li-ion battery recycles way faster than AAs and handles E-TTL/HSS perfectly tho. Honestly a total lifesaver for events.

I know everyone is saying Godox but since you asked about Yongnuo too I really think the Yongnuo YN685 II is worth a look for a more DIY budget setup. I have been using one with my 80D and it does the job without being super complicated although I am still basically a beginner when it comes to all the advanced lighting stuff and I mean it just works. Here are a couple of self-service tips that saved me some money:

• Check for firmware updates on the official site because that usually fixes any weird communication issues with the 90D shutter
• Dont bother buying expensive diffusers at first since a piece of white plastic or even a business card and a rubber band works amazingly well for bounce flash
• If the flash misfires just try cleaning the hot shoe contacts with a clean cloth because that fixes like 90 percent of the problems I have had Wait no I actually meant that it works for both bodies seamlessly so you wont have to keep changing settings when you swap. Its definitely a solid way to go if you want to save your cash for better glass later on!!

My buddy told me the exact same thing last week. Guess he was right lol.

Following this thread

> Honestly a total lifesaver for events. Seconding that! Just get any TTL flash from Godox for your 90D. Theyre amazing and soooo much cheaper than Canon stuff. Honestly, the value is just fantastic for indoor events!!

Totally agree that Godox has basically taken over the market for a reason. From a professional market research perspective, the gap between OEM Canon gear and third-party units has closed so much in the last five years that it's hard to justify those $500+ price tags for the 600EX-RT series anymore. While the V860 is great, I’d actually suggest looking at the Godox V1-C if you can swing the extra 30 bucks or so. The round head gives a way more natural fall-off for event work compared to the traditional rectangular heads. Also, if your on a super tight budget, the Yongnuo YN600EX-RT II is a solid clone of the Canon flagship and works perfectly with the 80D and 90D E-TTL system. Just keep in mind that the Godox 'X' radio system is way more expandable if you ever decide to move into off-camera lighting with larger AD-series strobes later. Honestly, for the price of one Canon speedlite, you could literally buy 3 Godox units and have a full multi-point setup. The reliability issues people used to talk about with third-party stuff are largely a thing of the past tbh.