You're confused a bit. Let me clarify some stuff.
"Civilian" firearm in forms of mostly precision rifles had been finding the way to army since the start of war in 2014. But that's it for army.
In 2022 with full scale invasion start in first days government declared "total resistance" with anyone without joining any unit would be able to use anything to kill russians. And this is where the most pics of civilian firearm came from. Because of fluid situation most ppl involved in volunteering help had some kind of guns - an in many cases they were civilian (in general in Ukraine it's legal to own long semiauto or long converted auto guns). At the same time many EU countries sent whatever they governments wanted/had to sent. FN FALs, Swedish SMGs, M14 from Baltic states, Grots from Poland, CZ Brens from Czech Republic. That was not an army procurement. Army did not lack small arms and it doesn't now. Interesting that International Legion first got some of those FNs. I think idea was to saturate civilian resistance with these guns (in Kyiv you could have just grab AK off the army truck with no documents asked, just take and get ready), however in a matter of months russians near Kyiv were massacred (you should read the stories, every night it was Open Season, very often unorganized, but very effective terror, when dozen of groups of civilians with guns with high motivation to kill and geared with night vision enter the area with russians - very few were taken as prisoners) and other retreated so everything was falling under army control and other government controlled units such as SBU (kind of FBI), TDF (Territorial Defense - volunteer light infantry units under Army command), Special forces of Police, etc. Some of these donated guns (that were modern) were redistributed. Some were provided to rear echelon units (like SMGs). Some into special forces organized by GUR (B&T and CZ Brens). Old stuff just disappeared (except those Swedish SMGs one can see with some artillery crews). Now civilian firearms are still widely carried by volunteers (medic, or other types) that are not officially part of any government units, I know it's hard to tell because all volunteers have same camo and gear, but they don't have unit identification patches. This is where you can see anything from Kel-Tec Sub to AR15. And of course expensive precision rifle come from both civilian market and from military aid from the world. Also, recalled, M14 were repurposed for some basic training, dunno what kind, I helped with modern stocks and did not asked after. Oh, yeah, another thing I recalled - it's quite relaxed in TDF and many have their own AR15s or AR10s instead of AK and technically you could do the same in regular army units but as I said it's mostly the case with precision rifles.
